Furthre work on PrettyPrinter

Fix wrong Node signature for String_Scalar created by T_STRING_VARNAME

Further work on PrettyPrinter

Replace yydebug flag with separate debug parser "ParserDebug"

Debugging shouldn't be necessairy normally, but carries a 25% performance overhead.

Fix some prettyprinting issues

Parse escape sequences in encapsed strings too

Further work on PrettyPrinter. Add possibility to test PrettyPrinter correctness

Fix incorrect Node creation for dynamic static property access

Further work on pretty printer

Parse strings more correctly, keep information on whether it was a single or double quoted string

Add initial implementation of pretty printer

Simplify grammar thus reducing shift/reduce conflicts

Fix parsing issue with array accesses on object accesses ($x->y[z])

Add LICENSE (BSD)

a) changes node structure (Stmt_, Expr_, ...) b) fixes parsing of x::$y[z]

Sorry for that one large commit. Won't happen again.

Slightly optimize the parser and improve the API

Initial commit