Tutorial: label basic features, precision 4%
Added step1-basic code
Added BrainDump config for step1-basic
Merge branch 'develop' into release-mindreader
Support multiword keywords
Step2-generic features, precision 1%
Merge branch 'release-mindreader' of github.com:HazyResearch/deepdive into release-mindreader
Fixed a str-int concat bug in gen_feats.py

In python2, str and int cannot be concatenated using "+" operator, and
it will cause bugs if dict_id is not assigned. (use auto-incr ids)
Convert to str() whenever possible to avoid TypeErrors
More use of str()
Convert get_sentence to use the unpack_words method and add functions to convert from one format of the dependencies to the other.
Reorganize and add comments
add regularization parameters for sampler
Merge pull request #183 from HazyResearch/feiran-regularization

add regularization parameter
Merge branch 'release-mindreader' of github.com:HazyResearch/deepdive into release-mindreader
Add regularization parameter documentation
Updated experiment for step2-generic-features, precision 44%
Add comments, pydoc to get_sentences, and a generic get_span function to retun a Span, just to improve the API a bit (it still sucks)
Improve the documentation for the generic features. This is going to be moved to the main doc directory in the next commit
Integrate generic features documentation in main DD doc. It still needs some improvements