Fix patterns containing newlines

Export "Grammar" class

Allows other packages to inherit from Grammar in order to programmatically define language grammars

Fix typo: s/repitition/repetition

Some grammars such as languag-git use fileTypes entries such as .git/config
to match Git config ...

implement applyEndPatternLast feature

Previously the captures ivar hash was passed in which was incorrect
since it must be the current...

Having multiple consecutive dots would make the selector invalid

Closes atom/language-make#6

This will handle both the $1 style and ${1:/downcase} styles in a
single replace call.

Change the maxTokensPerLine default option to Infinity

Previously these were unresolved so any $2 style markers were not
converted.

This will affect the value for each created grammar.

Previously the stack would be popped even when it contained a single rule
causing the next loop ...

Closes #8

Allows injections into the null grammar

This allows the null grammar to include injections

Support contentName in grammars

Closes #6