Expose showToken

closes #119
fix for #91
Fix EqualP pretty-printing
Add tests for #91
Seperate pragma and modifier with space

This is related to but does not at all fix https://github.com/haskell-suite/haskell-src-exts/issues/62
Replace remaining underscores between INLINE and CONLIKE with spaces
Tests for INLINE CONLIKE
don't chocke on Trustworthy extension
Added support for closed type families introduced in GHC 7.8
Test case for closed type families

Also found bugs while writing test cases.