[nvm run / nvm exec]: Silence "find nvmrc" output when `--silent` is provided.
[nvm run / nvm exec]: Silence "find nvmrc" output when `--silent` is provided.

Per https://github.com/creationix/nvm/issues/846#issuecomment-147588453
slariviere/nvm,edwmurph/nvm,thomasf/nvm,lukechilds/nvm,lukechilds/nvm,bevacqua/nvm,Kuzirashi/nvm,PeterDaveHello/nvm,Kuzirashi/nvm,ljharb/nvm,bevacqua/nvm,Theodeus/nvm,dfackler/nvm,evocateur/nvm,dfackler/nvm,PeterDaveHelloKitchen/nvm,creationix/nvm,creationix/nvm,tlevine/nvm,slariviere/nvm,fnogatz/swivm,Theodeus/nvm,jaawerth/nvm,jaawerth/nvm,tlevine/nvm,thomasf/nvm,PeterDaveHelloKitchen/nvm,PeterDaveHello/nvm,evocateur/nvm,ljharb/nvm,edwmurph/nvm