Unfinished commit that adds broken tests, and a broken parser.
Added file persistence layer, as alternative to postgres persistence layer.
Improve unit tests, rename chain to model.
Delete generated docs _build directory.
Refactor select into many smaller functions in utils.
Add some parser tests
Fix bugs in select.
pyparsing example
Fix more bugs in select the popped up as a result of refactoring.
Refactoring utils, and some cleanup.
Merge branch 'postgresdev' of github.com:mit-probabilistic-computing-project/BayesDB into postgresdev

Conflicts:
	bayesdb/engine.py
	bayesdb/utils.py
Fix indentation; refactoring
Merge branch 'master' into postgresdev

Conflicts:
	docs/_build/doctrees/bayesdb.doctree
	docs/_build/doctrees/environment.pickle
	docs/_build/doctrees/examples.doctree
	docs/_build/doctrees/gettingstarted.doctree
	docs/_build/html/_sources/examples.txt
	docs/_build/html/_sources/gettingstarted.txt
	docs/_build/html/bayesdb.html
	docs/_build/html/examples.html
	docs/_build/html/genindex.html
	docs/_build/html/gettingstarted.html
	docs/_build/html/objects.inv
	docs/_build/html/searchindex.js
Fix bugs
Merge branch 'master' into postgresdev
Add first pass at setup.py
update requirements.txt to make it clear that BayesDB depends on crosscat
Add basic implementation of estimate columns
Enforce that no BQL commands return just an integer
Passing select test