Use tuples with clauses, and only convert to lists if using an older version of pycosat
Start writing a heuristic for which algorithm to use
Correctly handle an empty equation in generate_constraints
Add a comment
Merge branch 'master' into lots-of-builds
Clearer error for 'conda search' with invalid regex

Closes gh-706

This prints a brief error message saying that the pattern was invalid,
rather than showing the full traceback.
Implement the swapping from minisatp

It doesn't really seem to make a difference, but I suppose it can't hurt.
Merge pull request #724 from takluyver/search-regex-err

Clearer error for 'conda search' with invalid regex
Add the ability to use PB to find the minimal SAT solutions

Conflicts:
	conda/logic.py
min_sat can't handle iterables any more

Handle empty clauses to min_sat
conda clean: Don't exit when there are no tarballs

There might be additional clean actions to perform.

Fixes #753.
Merge branch 'master' of github.com:conda/conda
Correctly chain clauses together
Make min_sat with alg!='iterate' do the right thing for unsatisfiable clauses
Fix min_sat
Correctly handle alternate min_sat algorithms in resolve
Allow to speed up bisection with evaluation
Use evaluate_func in min_sat
Allow to set the polarity for ITE and build_BDD

If only one polarity is used, then as many as half of the clauses may not be
needed.
Set the polarity for BDD in generate_constraints