test_file.py: move tests.py to test/test_file.py
PyFile: wrap FileMode

- Expose the enum FileMode
- Provide overloads for File::open with default mode
.travis.yml: Verbose unit testing
transmorgify: convert python list to vector
core.cc: some small additions for better testing
block.py: remove old test method
test: unit test for file and block
Merge pull request #6 from stoewer/unit-tests

Unit tests for file and block

LGTM!