Build submodel on top of existed model.
Move root node out of constructor.
Move root node out of constructor.
Reuse fix decomposition tree and mp model APIs.
Fix bug: the variable cannot be registered by the new name once the name was changed.
Return None as default decomposition tree.
Add max cliques decomposer. See <http://networkx.lanl.gov/reference/generated/networkx.algorithms.clique.find_cliques.html>.
Fix logging message.
Merge pull request #12 from d2rk/fix_mps_issues

Fix mps issues
Register max cliques decomposer. Update frontend solver protobuf.
Add logging message about selected decomposer.
Fix #11.
Add objective offset. Not yet fully implemented.
Merge pull request #13 from d2rk/fix_11

Fix #11
Merge branch 'master' into upstream
Merge branch 'upstream' into rbranch

Conflicts:
	src/main/python/les/decomposers/finkelstein_qb_decomposer.py