Some fixes I don't want to remember

Signed-off-by: Max Reitz <xanclic@niwohlos.org>
Add parser and syntax definition

+ The syntax probably still needs to be tweaked (and fixed) a bit (or
  replaced completely with something simpler and more useful); it's
  taken from the C++11 standard.
  Now, the syntax tree has to be contracted in some way and made use of.

Signed-off-by: Max Reitz <xanclic@niwohlos.org>