Add target to build single module
Add target to build single module

Summary:
Add a module target to the src Makefile that builds a single module and
its dependencies, perhaps with extra flags.  Useful for generating
assembly or interfaces, as well as directing the typechecker when
refactoring.

Execute: `make INFER_CFLAGS=<flags> M=<Module>.cm{o,x} module`

Reviewed By: jeremydubreil

Differential Revision: D3273437

fb-gh-sync-id: 65a51d6
fbshipit-source-id: 65a51d6

facebook/infer,facebook/infer,xennygrimmato/infer,kageiit/infer,kageiit/infer,ryoon/infer,kageiit/infer,blzq/infer,ryoon/infer,blzq/infer,jvillard/infer,facebook/infer,jvillard/infer,blzq/infer,ryoon/infer,facebook/infer,kageiit/infer,xennygrimmato/infer,xennygrimmato/infer,ryoon/infer,blzq/infer,jvillard/infer,ropas/infer,xennygrimmato/infer,ropas/infer,kageiit/infer,jsachs/infer,jsachs/infer,xennygrimmato/infer,ropas/infer,ryoon/infer,kageiit/infer,ropas/infer,jsachs/infer,ryoon/infer,xennygrimmato/infer,ropas/infer,facebook/infer,blzq/infer,jvillard/infer,jvillard/infer,facebook/infer,jsachs/infer,facebook/infer,jsachs/infer,blzq/infer,ropas/infer,jsachs/infer,kageiit/infer,xennygrimmato/infer,jvillard/infer,jvillard/infer