test runner: CUI runner - if tests failed, call exit (by default); if
called VTEST_CUI_ignore_test_failure called then return error code.
butils: realpath does not deal with non existing path names - do
something similar that is more portable;
cothread: cygwin: optimization killed check for jmpbuf index that
contains SP;
building of libevent was broken in x86_84
fix compilation error on x86_64
fix complation errors on Cygwin
fix compilation errors on x86_64
fix compilation on x86_64