various: remove the "dyncall", its tests and mentions in text-files

Well, you asked for it. I'm always happy to remove code ;-)

I hopefully got everything... looked for:

- git grep functions
- git grep DYNCALL
- git grep dyncall
- git grep test_ruby

still compiles, and all test-suits still pass (tested with the fixed
"try-to-fix-testsuite" branch)

But this still could break other packages, using this obscure feature in typelib?

Signed-off-by: Martin Zenzes <martin.zenzes@dfki.de>