Fix totality of updateWith/rebuildEnv in Effects
New size change graph builder
Looks at patterns, rather than case tree, and therefore finds it easier to
spot structurally smaller arguments which are more complex.
Fix Data.Bits: properly convert to machine-buitin types everywhere.
Fix Codegen: Shr is now called LShr, emit that.
Merge branch 'master' of git://github.com/edwinb/Idris-dev
Merge pull request #322 from raichoo/javascript

javascript: make FFI work with HOFs
Merge pull request #324 from andreas23/master

Fix for Data.Bits
javascript: added javascript lib package