Added a Writeable class
testing constants
Updated grammar rules
Merge branch 'master' into core

Conflicts:
	LamParsec.hs
	lambda.hs
Exp now deriving Show
Now translating lambda expression to valid Haskell
LamTranslator now writing translations to a file.

Example:

*LamTranslator> translate "example.lam"
*LamTranslator> :!ls
example.lam  example.hs
Added a directory for lambda files, now contains a single
example
Update README.md