updates to README
updates to README


Former-commit-id: 231f628a894034eb2b322cd3bb14338f3218a233
xunzhang/dynet,shuheik/dynet,clab/dynet,xunzhang/dynet,danielhers/dynet,clab/dynet,clab/cnn,clab/cnn,shuheik/dynet,clab/dynet,shuheik/dynet,shuheik/dynet,chunyang-wen/dynet,clab/dynet,chunyang-wen/dynet,shuheik/dynet,clab/dynet,xunzhang/dynet,danielhers/dynet,clab/dynet,xunzhang/dynet,danielhers/dynet,clab/cnn,danielhers/dynet,shuheik/dynet,danielhers/dynet,danielhers/dynet,shuheik/dynet,clab/dynet,danielhers/dynet,chunyang-wen/dynet,chunyang-wen/dynet