Split exception handling in deh/deh_win32/deh_win64_posix

The original file names (deh and deh2) are not very descriptive. This
structure is inspired by the section and section_xxx modules.

_d_createTrace() implementation is left in the deh module because is
common to all the architectures.
int array ops: Removed redundant checks & scalar
Merge pull request #565 from leandro-lucarella-sociomantic/deh-split

Split exception handling in deh/deh_win32/deh_win64_posix
simplify link arguments for the unittest .so
remove support for weak _d_dso_registry linking

- dmd now emits normal references for _d_dso_registry
reinstated checks and set x64 mmx/sse/sse2 enums
fix formatting
More formatting fixes

there's gonna be some bug reports in emacs d-mode for this...
tabs and spaces...
trailing whitespace
removed unused labels
whitespace again
Merge pull request #566 from John-Colvin/patch-2

int array ops: Removed redundant checks & scalar asm
version typo
Merge pull request #570 from John-Colvin/patch-3

arrayint.d version typo
Merge pull request #569 from dawgfoto/removeWeakLinkage

remove support for weak _d_dso_registry linking
Merge pull request #567 from dawgfoto/fullPathForSOLinking

simplify link arguments for the unittest .so