Add constraint stuff to Moe config.
Add __init__.py to constraint directory.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72666209
Add constraintvm with simple tests.
Tweaks to other files to get everything working.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=72678836
Add experimental SAT encoder for subtype constraint solving.
Implement simple self binding in constraint types by stripping self parameter.
Fix multiple small bugs in constraint types.py.
Add support for setting initial polarity to SATProblem.
(Also sneak in Moe db update)
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73658319
Add constraint encoder that generates Prolog (called the Datalog encoder because the encoding is in fact data log except for one small convenience).
Make XSB visible from my project so I can call into it.
Also fix some bugs in the constraintvm (noteably it was generating constraints in the wrong direction when an attribute was assigned to).

Note: This code is very experimental, but I think it demonstrates an interesting approach and may serve as the basis for another first order solver for type constraints.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73732383
Add a test that shows the failure due to the stack not being rewound.
Add notes on how to fix it addressed to kramm.
Add comment listing missing features in []VM.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73820553
Remove log object from pytypedecl as per request from <user>@.
I did not remove them from byterun because they match the upstream style of the project.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=73904233
Add missing file.
Merge branch 'moe_writing_branch_from_ce4b232d7d2bd2fd4dee5c172fefb5451ca594cd' into constraint (replacing all files)

Conflicts:
	byterun/constraint/constraint_store.py
	byterun/constraint/constraintvm.py
	byterun/constraint/types.py
	tests/test_constraint_pytd.py
	tests/test_constraintvm.py