* math: Setting the bits of floating-point numbers
Added macros which set all 32 bits of a float, the lower 32 bits of
a double, and the upper 32 bits of a double. Some changes were made to
older code to use these macros.
* Replaced code with bitsetting macros in __tan.c3 and tan.c3
* math: tests for word macros and release notes
Tests were written for the word macros, which include getting and
setting a float with a uint and getting and setting the high or low word
of a double with a uint.
Release notes were updated to include the word setter macros.
* C3_MATH feature
This feature allows the usage of noclib math files even when libc is in use.
If a nolibc symbol exists, it will be used in place of libc, otherwise
it will default to libc.
* Added MIT License notices to atan.c3
