print installed ocamlfind packages in Travis
print installed ocamlfind packages in Travis

Summary:
the build logs don't contain enough info to know which version of
dependencies we have installed. this will print all of them plus their versions.

Reviewed By: gabelevi

Differential Revision: D4637636

fbshipit-source-id: e54ca0793e1449a6570719c43d59a564b2c1dd83

AgentME/flow,AgentME/flow,facebook/flow,samwgoldman/flow,mroch/flow,mroch/flow,MichaelDeBoey/flow,gabelevi/flow,nmote/flow,popham/flow,nmote/flow,jamesgpearce/flow,TiddoLangerak/flow,gabro/flow,gabro/flow,claudiopro/flow,gabro/flow,popham/flow,samwgoldman/flow,JonathanUsername/flow,ylu1317/flow,gabelevi/flow,AgentME/flow,gabro/flow,fletcherw/flow,samwgoldman/flow,mroch/flow,claudiopro/flow,JonathanUsername/flow,jamesgpearce/flow,facebook/flow,samwgoldman/flow,fletcherw/flow,JonathanUsername/flow,mroch/flow,jamesgpearce/flow,jamesgpearce/flow,popham/flow,fletcherw/flow,gabelevi/flow,samwgoldman/flow,fletcherw/flow,ylu1317/flow,MichaelDeBoey/flow,ylu1317/flow,MichaelDeBoey/flow,nmote/flow,gabro/flow,claudiopro/flow,samwgoldman/flow,fletcherw/flow,TiddoLangerak/flow,claudiopro/flow,nmote/flow,samwgoldman/flow,mroch/flow,gabelevi/flow,JonathanUsername/flow,gabelevi/flow,facebook/flow,ylu1317/flow,claudiopro/flow,JonathanUsername/flow,jamesgpearce/flow,JonathanUsername/flow,popham/flow,gabro/flow,jamesgpearce/flow,facebook/flow,nmote/flow,mroch/flow,gabelevi/flow,TiddoLangerak/flow,popham/flow,nmote/flow,MichaelDeBoey/flow,MichaelDeBoey/flow,nmote/flow,facebook/flow,gabelevi/flow,TiddoLangerak/flow,mroch/flow,popham/flow,JonathanUsername/flow,ylu1317/flow,TiddoLangerak/flow,fletcherw/flow,AgentME/flow,facebook/flow,popham/flow,facebook/flow,AgentME/flow,jamesgpearce/flow