Initial work on parser bringup (squash)
Stuff
Parser work. Not sure whether to have a different class for each node or not.
Parser limps into existence
Merge branch 'master' into parsed
Rename expression.h to parse_tree.h and parse_exec.h
More work on new parser
Added parse builtin for testing. Lots of work on simulated execution.
Beginning support for new parser error messages
Merge branch 'master' into ast
Merge branch 'master' into ast
More work on simulating execution of parse trees. Pipes are totally screwed up.
More work on new parser
Merge branch 'master' into ast
More work on the AST. block statements worked out a bit more.
If statements parse
Implement support for switch
Fix for extra token_end
More work
Merge branch 'master' into ast_templates

Conflicts:
	fish_tests.cpp