Tag remaining specs (e.g. travis specific issue)
fixtures/file_types.rb is used on one addtional spec

Disables also "core/file/stat/ftype_spec.rb" as it results in a runtime error
on travis.
Merge pull request #830 from mswart/test_failures

Fixing / Tagging the current build errors
Removed a todo that was solved.

The TODO referred to those imports formerly having been from pypy, rather than RPython
Merge pull request #831 from topazproject/remove-todo

Removed a todo that was solved.
Fixed several typos
Merge pull request #832 from topazproject/typo-fix

Fixed several typos
Merge remote-tracking branch 'topaz/master' into ffi_structs
tests: adjust ffi tests to match implemented struct support