Revert "Source the nvm.sh file"
Revert "Source the nvm.sh file"

Fixes #826
This reverts commit b4151e1446f36d534a8a98e6876d293e05317173.

wahyutaufik/nvm,lukechilds/nvm,kumaria/nvm,kumaria/nvm,Richardphp/nvm,tlevine/nvm,elrasguno/nvm,Ingelheim/nvm,icyflame/nvm,tlevine/nvm,jaawerth/nvm,PeterDaveHello/nvm,thomasf/nvm,nontage24/nvm,SampleLiao/nvm,PeterDaveHello/nvm,thomasf/nvm,elrasguno/nvm,mirydz/nvm,Richardphp/nvm,PeterDaveHelloKitchen/nvm,jaawerth/nvm,jhliberty/nvm,dfackler/nvm,lukechilds/nvm,hanhailong/nvm,jhliberty/nvm,ljharb/nvm,nontage24/nvm,bevacqua/nvm,youleiy/nvm,woss/nvm,Theodeus/nvm,Theodeus/nvm,Kuzirashi/nvm,bevacqua/nvm,hanhailong/nvm,wahyutaufik/nvm,gtdeng/nvm,tianzhihen/nvm,williamboman/nvm,edwmurph/nvm,slariviere/nvm,fnogatz/swivm,edwmurph/nvm,domenicosolazzo/nvm,woss/nvm,devedbox/nvm,dfackler/nvm,creationix/nvm,slariviere/nvm,evocateur/nvm,domenicosolazzo/nvm,SampleLiao/nvm,Kuzirashi/nvm,evocateur/nvm,PeterDaveHelloKitchen/nvm,icyflame/nvm,williamboman/nvm,ljharb/nvm,tianzhihen/nvm,mirydz/nvm,Ingelheim/nvm,creationix/nvm,devedbox/nvm,gtdeng/nvm,youleiy/nvm