scripts: Update .gitignore with entries from main repo.
scripts: Update .gitignore with entries from main repo.

BUG=none
TEST=none
TBR=anush

Review URL: http://codereview.chromium.org/2724012

nicescale/scripts,andrejro/coreos--scripts,mischief/scripts,glevand/coreos--scripts,sigma/coreos-scripts,marineam/coreos-scripts,endocode/scripts,BugRoger/scripts,crawford/scripts,BugRoger/scripts,endocode/scripts,smilart/scripts,glevand/coreos--scripts,andrejro/coreos--scripts,marineam/coreos-scripts,nicescale/scripts,crawford/scripts,mjg59/scripts,mjg59/scripts,sigma/coreos-scripts,crawford/scripts,sigma/coreos-scripts,BugRoger/scripts,marineam/coreos-scripts,coreos/scripts,nicescale/scripts,smilart/scripts,gtank/scripts,trnubo/scripts,fivethreeo/scripts,mischief/scripts,vmware/coreos-scripts,andrejro/coreos--scripts,fivethreeo/scripts,vmware/coreos-scripts,bcwaldon/coreos-scripts,coreos/scripts,mjg59/scripts,gtank/scripts,trnubo/scripts,smilart/scripts,bcwaldon/coreos-scripts,zhang0137/scripts,trnubo/scripts,fivethreeo/scripts,vmware/coreos-scripts,zhang0137/scripts,bcwaldon/coreos-scripts,gtank/scripts,mischief/scripts,zhang0137/scripts,endocode/scripts