Replace the bash selftest plumbing with CTest.
To use the selftests, build with -DLWS_WITH_MINIMAL_EXAMPLES=1
and `CTEST_OUTPUT_ON_FAILURE=1 make test` or just
`make test`.
To disable tests that require internet access, also give
-DLWS_CTEST_INTERNET_AVAILABLE=0
Remove travis and appveyor scripts on master.
Remove travis and appveyor decals on README.md.
Add support for external pthreads lib on windows and some docs about how to do.
It can build with LWS_WITH_THREADPOOL and LWS_WITH_MINIMAL_EXAMPLES including the
pthreads-dependent ones without warnings or errors on windows platform as well with this.
pthreads_t can be anything, including a struct - not a pointer-to-a-struct
but the struct itself. These can't be cast to a void * for printing as they can
on linux, where the base type is a pointer.
Let's fix all the usage of those to determine their own thread index in terms
of the meaning to the program rather than as a tid.
