Some recipes require the headers, but they don't explicitly say
so. Parallel make (-j`nproc`) might start compiling the libs when the
headers aren't done yet.

Add completely untested redox epoll implementation

See merge request !211

Implement rand_r(), strnlen_s(), tempnam(), tmpnam()

See merge request !210

Handle zero len for strerror_r

See merge request !209

Resolve "BufferedVaList::index may read out of bounds"

Closes #140

See merge request !208