Implement lambda expressions

Conflicts:
	src/codegen/irgen/hooks.cpp
	src/codegen/irgen/irgenerator.cpp

Conflicts:
	src/codegen/irgen/hooks.cpp
	src/codegen/irgen/irgenerator.cpp
	src/core/types.h

Not completely correct/working yet, but finally start
doing classes the right way.

Should probably give up on hacking it like this
and just handle classdef scopes for real.

Some basic fixes

(was previously only working at the global scope)

Pretty similar to #78

- find could not possibly have worked prior

(Though most libraries will probably crash)

Fix make check: Order includes alphabetical

Fix reversing of >, <, <= and >= compare operations

Just noticed that they are also wrong

Required a bit of refactoring in terms of how
parameter specifiers are passed around.

Well not sure if it's a deadlock; I think we try to
re-entrantly acquire the codegen lock, which then
confuses it later?

GC: Register None

Implement chained comparisons

Merges #88

Conflicts:
	src/core/threading.cpp

Not sure why greg_t got changed from 'long' to 'long long' in newer versions of glibc; just cast it to be compatible

Build fix