More JMPSTUB rationalization of inline functions.
Add implementation of mkstemp() and mkdtemp() functions.
Minor formatting adjustment.
Layout and documentary corrections.
Adjust header guards to resolve issue [#2244].
Correct complex square root computation per issue [#2246].
Correct complex arcsin computation per issue [#2245].
Don't implicitly define _POSIX_C_SOURCE too early.
More rationalization of CRT_INLINE function implementations.
Another CRT_INLINE function implementation rationalization.
Some POSIX feature test adjustments.
Some further inline function rationalization.
Delete an unnecessary Unicode wrapper file.