Add /.vagrant to .gitignore.
Add /.vagrant to .gitignore.

Signed-off-by: Christian Williams <c8e012a832cdeaee1d1428d27b803f9a7e99f710@pivotal.io>

allomov/bosh-agent,karafelix/bosh-agent,karafelix/bosh-agent,pivotal-nader-ziada/bosh-agent,Altoros/bosh-agent,alex8023/bosh-agent,pivotal-nader-ziada/bosh-agent,tacgomes/bosh-agent,pivotal-nader-ziada/bosh-agent,alex8023/bosh-agent,gu-bin/bosh-agent,mattcui/bosh-agent,mattcui/bosh-agent,Altoros/bosh-agent,evanfarrar/bosh-agent,cloudfoundry/bosh-agent,uzzz/bosh-agent,uzzz/bosh-agent,gu-bin/bosh-agent,cloudfoundry/bosh-agent,karafelix/bosh-agent,uzzz/bosh-agent,evanfarrar/bosh-agent,evanfarrar/bosh-agent,allomov/bosh-agent,tacgomes/bosh-agent,Altoros/bosh-agent,gu-bin/bosh-agent,allomov/bosh-agent,tacgomes/bosh-agent,alex8023/bosh-agent,mattcui/bosh-agent