Merge pull request #11 from ariccio/fix-blank-header-ctrl

Fixes #8 (sorting issue)

STATIC_DOWNCAST broke, for some reason

Grr. It said that CDirstatApp didn't have a member named
`classCDirstatApp`. I'm pretty sure this has to do with MFC message-map
nonsense.

minor tweaks, a few hacks that'll go away soon

small tweaks to COLOR_DEBUGGING, other refactoring

Attempt at addressing issue #1, release 0.9.1

I've audited every single use of std::terminate( )/abort( ) (this is why
I keep the codebase small!), an ensured that at the very least, some
form of error message is displayed before any termination, no matter how
unexpected.

Also fixed my own idiotic use of `void displayWindowsMsgBoxWithMessage(
PCWSTR )` whereby I'd construct a std::wstring from a (wide) string
literal, then move it into `void displayWindowsMsgBoxWithMessage( const
std::wstring )`. What the hell was I doing??

Lastly, I disabled AVX generation, and now uses the SSE2 option for 32
bit builds, and the DEFAULT option for 64 bit builds. All 64 bit
processors have SSE2 built in, and MSVC doesn't even recognize
`/arch:SSE2` when building a 64 bit executable.

Hopefully this addresses the issue!

automatic memory management, tweaked annotations