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>
Removing this one is problematic ... We can probably Type.wrap a string generated with String#pack, e.g.

'''
reg = Typelib::CXXRegistry.new
double_t = reg.get('/double')
nan_d = [Float::NAN].pack("d")
assert double_t.wrap(nan_d).to_ruby.nan?
float_t = reg.get('/float')
nan_f = [Float::NAN].pack("f")
assert float_t.wrap(nan_f).to_ruby.nan?
'''