cmake: rewrite the build options and the flag setting

[illwieckz]

Rewrite the options and the flag setting

• Add USE_LTO to enable LTO, enabled by default.
• Add USE_EXTRA_OPTIMIZATION to also enable -O3 when it is not used by default enabled by default.
• Add USE_FAST_MATH, to produce reproducible CRN files this should be disabled, enabled by default.
• Increase warning verbosity level.
• Generate maximum amount of debug information, including macro definitions.
• Always disable strict aliasing, the code requires it to always be disabled.

Fixes #29:

• https://github.com/DaemonEngine/crunch/issues/29

[illwieckz]

This also changes spaces for the 5% of the remaining untouched code. I was annoyed by the whitespace ascii art and anyway I almost rewrote everything.

[slipher]

LGTM