output cython html by default
add more files to gitignore
make setup.py executable
improve definitions file:
handle exceptions, add constants, fix some types
(unfinished) rewrite:

* move most things to Cython;
* drop sklearn-like class, at least for now;
* add tests;
* setup tox.

Tagger is not ready yet. Before running tests run ./update_cpp.sh
(updated cpp wrapper is not commited).
added support for trainer message handling
Rename Trainer.message to Traier.on_message; log messages by default.
DOC better docstrings for append_dicts and append_stringlists methods
add a workaround for one more case where CRFSuite segfaults
type casting for training parameters
more robust exception handling in on_message
better function signature
allow setting Trainer parameters in constructor
rename Trainer.on_message back to message to better match C++ code
Tagger.open, Tagger.close and Tagger.labels
test_wrapper -> test_pycrfsuite
CRFSuiteTrainError -> CRFSuiteError
add one more test that shows a possible segfault
use ValueError because we're checking that file can be opened ourselves
prediction support (unfinished & untested)