Made README a markdown file. Content is the same, readability with
text-based applications is identical, but github renders this way more
nicely. :)

Conflicts:
	README
cmake: rework unit test execution a bit

so we don't depend on the static test_exec_monitor boost lib, also fixes
some rare main undefined errors

Conflicts:
	CMakeLists.txt
	cmake/modules/macros.cmake
travis: update apt tree before installing

this will fix errors in apt-get install if the server no longer have the requested archives