Conditionally enable test for OCaml findlib

Closes #157
Conditionally enable test for Python setuptools

Closes #162
Conditionally enable tests with the Mingw32 cross-compiler

Closes #158
Conditionally enable tests using noweb
Write a more portable version of texmf test
Merge branch 'topic/condtionally-enable-tests' 'topic/texmf-jessie'