add add_to_path shell function in build.sh
add add_to_path shell function in build.sh

requires 1 arg - new path,
add it to the PATH only once (script is called repetitively)
eg add_to_path /home/joe/nta/eng

BeiLuoShiMen/nupic,mcanthony/nupic,vamsirajendra/nupic,loretoparisi/nupic,pulinagrawal/nupic,rayNymous/nupic,chen0031/nupic,BoltzmannBrain/nupic,metaml/nupic,passiweinberger/nupic,alfonsokim/nupic,eranchetz/nupic,pulinagrawal/nupic,ywcui1990/nupic,cngo-github/nupic,vamsirajendra/nupic,metaml/nupic,neuroidss/nupic,mcanthony/nupic,allanino/nupic,BoltzmannBrain/nupic,runt18/nupic,virneo/nupic,cngo-github/nupic,brev/nupic,fergalbyrne/nupic,go-bears/nupic,glorizen/nupic,cogmission/nupic,lscheinkman/nupic,wanghaven/nupic,fergalbyrne/nupic,blueburningcoder/nupic,jcasner/nupic,jcasner/nupic,cogmission/nupic,virneo/nupic,marionleborgne/nupic,rhyolight/nupic,chen0031/nupic,EricSB/nupic,loretoparisi/nupic,breznak/nupic,loretoparisi/nupic,rhyolight/nupic,sambitgaan/nupic,pap/nupic,eranchetz/nupic,badlogicmanpreet/nupic,pulinagrawal/nupic,darshanthaker/nupic,allanino/nupic,alfonsokim/nupic,rcrowder/nupic,SaganBolliger/nupic,ben-hopps/nupic,GeraldLoeffler/nupic,badlogicmanpreet/nupic,glorizen/nupic,arhik/nupic,marionleborgne/nupic,rayNymous/nupic,vamsirajendra/nupic,numenta/nupic,glorizen/nupic,vitaly-krugl/nupic,subutai/nupic,lscheinkman/nupic,wanghaven/nupic,virneo/nupic,wanghaven/nupic,runt18/nupic,markneville/nupic,rcrowder/nupic,ywcui1990/nupic,chanceraine/nupic,chanceraine/nupic,scottpurdy/nupic,allanino/nupic,ben-hopps/nupic,numenta/nupic,subutai/nupic,breznak/nupic,arhik/nupic,cogmission/nupic,elkingtonmcb/nupic,badlogicmanpreet/nupic,scottpurdy/nupic,brev/nupic,lscheinkman/nupic,brev/nupic,mcanthony/nupic,GeraldLoeffler/nupic,runt18/nupic,EricSB/nupic,vitaly-krugl/nupic,SaganBolliger/nupic,eranchetz/nupic,blueburningcoder/nupic,EricSB/nupic,akhilaananthram/nupic,cngo-github/nupic,chanceraine/nupic,rayNymous/nupic,pap/nupic,breznak/nupic,numenta/nupic,passiweinberger/nupic,ywcui1990/nupic,BeiLuoShiMen/nupic,metaml/nupic,akhilaananthram/nupic,neuroidss/nupic,sambitgaan/nupic,go-bears/nupic,darshanthaker/nupic,pap/nupic,akhilaananthram/nupic,darshanthaker/nupic,sambitgaan/nupic,GeraldLoeffler/nupic,numenta-ci/nupic,markneville/nupic,rcrowder/nupic,BoltzmannBrain/nupic,go-bears/nupic,BeiLuoShiMen/nupic,blueburningcoder/nupic,arhik/nupic,subutai/nupic,neuroidss/nupic,elkingtonmcb/nupic,fergalbyrne/nupic,scottpurdy/nupic,numenta-ci/nupic,alfonsokim/nupic,markneville/nupic,passiweinberger/nupic,vitaly-krugl/nupic,jcasner/nupic,marionleborgne/nupic,chen0031/nupic,ben-hopps/nupic,SaganBolliger/nupic,elkingtonmcb/nupic,numenta-ci/nupic,rhyolight/nupic