Fixed a bunch of bugs with return/break/continue in loops.
Fixed support for the DMDFE hidden implicit return value variable. This can be needed for some foreach statements where the loop body is converted to a nested delegate, but also possibly returns from the function.
Added std.math to phobos.
Added AA runtime support code, done ground work for implementing AAs.
Several other bugfixes.
Added initial support for CatExp aka 'a ~ b'
Fixed global constant static arrays initialized with string literals
Fixed casting any dynamic array to void*
Fixed new expression with temporary storage
Fixed alias declarations in function scope
Fixed relational comparisons of pointers
