Add make install
Add make install

Summary:
Add make install.  If INSTALL_PATH is not set, then rocksdb will be
installed under "/usr/local" directory (/usr/local/include for headers
and /usr/local/lib for library file(s).)

Test Plan:
Develop a simple rocksdb app, called test.cc, and do the followings.

make clean
make static_lib -j32
sudo make install
g++ -std=c++11 test.cc -lrocksdb -lbz2 -lz -o test
./test

sudo make uninstall
make clean
make shared_lib -j32
sudo make install
g++ -std=c++11 test.cc -lrocksdb -lbz2 -lz -o test
./test

make INSTALL_PATH=/tmp/path install
make INSTALL_PATH=/tmp/path uninstall
and make sure things are installed / uninstalled in the specified path.

Reviewers: ljin, sdong, igor

Reviewed By: igor

Subscribers: leveldb

Differential Revision: https://reviews.facebook.net/D23211

vmx/rocksdb,lgscofield/rocksdb,NickCis/rocksdb,lgscofield/rocksdb,Andymic/rocksdb,flabby/rocksdb,RyanTech/rocksdb,dkorolev/rocksdb,norton/rocksdb,SunguckLee/RocksDB,IMCG/RcoksDB,tizzybec/rocksdb,siddhartharay007/rocksdb,wlqGit/rocksdb,fengshao0907/rocksdb,amyvmiwei/rocksdb,virtdb/rocksdb,Applied-Duality/rocksdb,Andymic/rocksdb,jalexanderqed/rocksdb,hobinyoon/rocksdb,SunguckLee/RocksDB,NickCis/rocksdb,lgscofield/rocksdb,flabby/rocksdb,zhangpng/rocksdb,skunkwerks/rocksdb,rDSN-Projects/rocksdb.replicated,Applied-Duality/rocksdb,anagav/rocksdb,IMCG/RcoksDB,kaschaeffer/rocksdb,norton/rocksdb,siddhartharay007/rocksdb,jalexanderqed/rocksdb,JohnPJenkins/rocksdb,alihalabyah/rocksdb,bbiao/rocksdb,luckywhu/rocksdb,geraldoandradee/rocksdb,JackLian/rocksdb,virtdb/rocksdb,zhangpng/rocksdb,ryneli/rocksdb,caijieming-baidu/rocksdb,flabby/rocksdb,amyvmiwei/rocksdb,Andymic/rocksdb,vmx/rocksdb,facebook/rocksdb,facebook/rocksdb,biddyweb/rocksdb,fengshao0907/rocksdb,luckywhu/rocksdb,skunkwerks/rocksdb,JoeWoo/rocksdb,IMCG/RcoksDB,dkorolev/rocksdb,norton/rocksdb,lgscofield/rocksdb,luckywhu/rocksdb,norton/rocksdb,jalexanderqed/rocksdb,amyvmiwei/rocksdb,wlqGit/rocksdb,facebook/rocksdb,makelivedotnet/rocksdb,IMCG/RcoksDB,virtdb/rocksdb,ryneli/rocksdb,zhangpng/rocksdb,wat-ze-hex/rocksdb,mbarbon/rocksdb,JoeWoo/rocksdb,Andymic/rocksdb,mbarbon/rocksdb,Vaisman/rocksdb,rDSN-Projects/rocksdb.replicated,kaschaeffer/rocksdb,bbiao/rocksdb,tsheasha/rocksdb,OverlordQ/rocksdb,SunguckLee/RocksDB,caijieming-baidu/rocksdb,wenduo/rocksdb,dkorolev/rocksdb,tsheasha/rocksdb,bbiao/rocksdb,makelivedotnet/rocksdb,wlqGit/rocksdb,wskplho/rocksdb,JohnPJenkins/rocksdb,sorphi/rocksdb,zhangpng/rocksdb,Andymic/rocksdb,hobinyoon/rocksdb,siddhartharay007/rocksdb,skunkwerks/rocksdb,kaschaeffer/rocksdb,wat-ze-hex/rocksdb,tsheasha/rocksdb,temicai/rocksdb,alihalabyah/rocksdb,wskplho/rocksdb,SunguckLee/RocksDB,anagav/rocksdb,vashstorm/rocksdb,fengshao0907/rocksdb,IMCG/RcoksDB,lgscofield/rocksdb,Vaisman/rocksdb,amyvmiwei/rocksdb,fengshao0907/rocksdb,wenduo/rocksdb,JohnPJenkins/rocksdb,mbarbon/rocksdb,JackLian/rocksdb,alihalabyah/rocksdb,wskplho/rocksdb,kaschaeffer/rocksdb,bbiao/rocksdb,wenduo/rocksdb,wskplho/rocksdb,wat-ze-hex/rocksdb,mbarbon/rocksdb,jalexanderqed/rocksdb,geraldoandradee/rocksdb,OverlordQ/rocksdb,makelivedotnet/rocksdb,OverlordQ/rocksdb,rDSN-Projects/rocksdb.replicated,hobinyoon/rocksdb,IMCG/RcoksDB,wenduo/rocksdb,luckywhu/rocksdb,rDSN-Projects/rocksdb.replicated,temicai/rocksdb,caijieming-baidu/rocksdb,jalexanderqed/rocksdb,tsheasha/rocksdb,Applied-Duality/rocksdb,SunguckLee/RocksDB,OverlordQ/rocksdb,rDSN-Projects/rocksdb.replicated,temicai/rocksdb,siddhartharay007/rocksdb,Vaisman/rocksdb,sorphi/rocksdb,SunguckLee/RocksDB,zhangpng/rocksdb,biddyweb/rocksdb,norton/rocksdb,biddyweb/rocksdb,sorphi/rocksdb,ryneli/rocksdb,sorphi/rocksdb,ylong/rocksdb,jalexanderqed/rocksdb,kaschaeffer/rocksdb,facebook/rocksdb,Applied-Duality/rocksdb,JackLian/rocksdb,dkorolev/rocksdb,caijieming-baidu/rocksdb,vashstorm/rocksdb,biddyweb/rocksdb,tsheasha/rocksdb,alihalabyah/rocksdb,anagav/rocksdb,vashstorm/rocksdb,tizzybec/rocksdb,SunguckLee/RocksDB,vmx/rocksdb,wskplho/rocksdb,vmx/rocksdb,norton/rocksdb,makelivedotnet/rocksdb,geraldoandradee/rocksdb,vmx/rocksdb,skunkwerks/rocksdb,tizzybec/rocksdb,caijieming-baidu/rocksdb,temicai/rocksdb,fengshao0907/rocksdb,vashstorm/rocksdb,wlqGit/rocksdb,Applied-Duality/rocksdb,temicai/rocksdb,tsheasha/rocksdb,Applied-Duality/rocksdb,alihalabyah/rocksdb,caijieming-baidu/rocksdb,vmx/rocksdb,virtdb/rocksdb,RyanTech/rocksdb,luckywhu/rocksdb,NickCis/rocksdb,biddyweb/rocksdb,anagav/rocksdb,bbiao/rocksdb,siddhartharay007/rocksdb,NickCis/rocksdb,flabby/rocksdb,temicai/rocksdb,wskplho/rocksdb,tizzybec/rocksdb,JoeWoo/rocksdb,tsheasha/rocksdb,siddhartharay007/rocksdb,JackLian/rocksdb,kaschaeffer/rocksdb,JohnPJenkins/rocksdb,norton/rocksdb,amyvmiwei/rocksdb,JohnPJenkins/rocksdb,hobinyoon/rocksdb,JoeWoo/rocksdb,ylong/rocksdb,wenduo/rocksdb,flabby/rocksdb,skunkwerks/rocksdb,wlqGit/rocksdb,RyanTech/rocksdb,vashstorm/rocksdb,geraldoandradee/rocksdb,geraldoandradee/rocksdb,alihalabyah/rocksdb,rDSN-Projects/rocksdb.replicated,tizzybec/rocksdb,ryneli/rocksdb,JohnPJenkins/rocksdb,RyanTech/rocksdb,vashstorm/rocksdb,makelivedotnet/rocksdb,tsheasha/rocksdb,hobinyoon/rocksdb,ryneli/rocksdb,zhangpng/rocksdb,mbarbon/rocksdb,biddyweb/rocksdb,OverlordQ/rocksdb,Andymic/rocksdb,mbarbon/rocksdb,Andymic/rocksdb,OverlordQ/rocksdb,wenduo/rocksdb,Vaisman/rocksdb,anagav/rocksdb,virtdb/rocksdb,RyanTech/rocksdb,facebook/rocksdb,rDSN-Projects/rocksdb.replicated,tizzybec/rocksdb,OverlordQ/rocksdb,dkorolev/rocksdb,JackLian/rocksdb,facebook/rocksdb,bbiao/rocksdb,luckywhu/rocksdb,JohnPJenkins/rocksdb,wlqGit/rocksdb,norton/rocksdb,biddyweb/rocksdb,Applied-Duality/rocksdb,Vaisman/rocksdb,Andymic/rocksdb,hobinyoon/rocksdb,makelivedotnet/rocksdb,facebook/rocksdb,hobinyoon/rocksdb,RyanTech/rocksdb,lgscofield/rocksdb,alihalabyah/rocksdb,siddhartharay007/rocksdb,fengshao0907/rocksdb,flabby/rocksdb,wat-ze-hex/rocksdb,geraldoandradee/rocksdb,wat-ze-hex/rocksdb,SunguckLee/RocksDB,virtdb/rocksdb,amyvmiwei/rocksdb,zhangpng/rocksdb,NickCis/rocksdb,RyanTech/rocksdb,lgscofield/rocksdb,JoeWoo/rocksdb,Vaisman/rocksdb,virtdb/rocksdb,jalexanderqed/rocksdb,vashstorm/rocksdb,JackLian/rocksdb,wenduo/rocksdb,sorphi/rocksdb,wat-ze-hex/rocksdb,ylong/rocksdb,wat-ze-hex/rocksdb,vmx/rocksdb,luckywhu/rocksdb,ylong/rocksdb,ylong/rocksdb,wat-ze-hex/rocksdb,IMCG/RcoksDB,wskplho/rocksdb,hobinyoon/rocksdb,anagav/rocksdb,temicai/rocksdb,skunkwerks/rocksdb,ryneli/rocksdb,bbiao/rocksdb,kaschaeffer/rocksdb,NickCis/rocksdb,amyvmiwei/rocksdb,NickCis/rocksdb,wenduo/rocksdb,sorphi/rocksdb,wlqGit/rocksdb,skunkwerks/rocksdb,ryneli/rocksdb,anagav/rocksdb,geraldoandradee/rocksdb,dkorolev/rocksdb,makelivedotnet/rocksdb,ylong/rocksdb,mbarbon/rocksdb,tizzybec/rocksdb,ylong/rocksdb,vmx/rocksdb,JoeWoo/rocksdb,sorphi/rocksdb,Vaisman/rocksdb,dkorolev/rocksdb,JoeWoo/rocksdb,caijieming-baidu/rocksdb,flabby/rocksdb,fengshao0907/rocksdb,bbiao/rocksdb,facebook/rocksdb,JackLian/rocksdb