VSIX tooling changes to support Visual Studio 2013.
Use the target platorm version in the VS props file as well.
Update comments and package flavor error message.
More changes to support MSVC 18.
Use the VisualStudioVersion variable instead of _MSC_VER.
More corrects to VS 2013 integration.
Environment variable names in nmake must be in all uppercase.
Initial implementation of the unlikely() SQL function used as a hint to
the query planner.
Enhance the plan solver to take into account the number of output rows when
computing the set of paths to retain for the next cycle.
Continuing refinements of the logic to take WHERE clause terms not used for
indexing into account when computing the number of output rows from each
table.
Make sure that the transitive constraint optimization does not cause
WHERE clause terms to be disabled prematurely.  We are unable to find a test
case that fails because of this, but it seems prudent to make this
preventative change nevertheless.
Deterministically initialize the PRNG used as a tie-breaker in the ANALYZE
command, so that the analysis is always the same given the same database.
This simplifies testing.
Merge trunk fixes into the unlikely-func branch.
Tweaks to the index selection logic.
Change the name of the two-argument unlikely() function to likelihood().
Add test cases.
Additional unlikely() test cases.  Logic tweaks to support test coverage.
Add test cases to cover TPC-H Q8.
Improvements to likelihood processing so that commuting an unindexed term in
the WHERE clause does not change the query plan.
Merge updates from trunk.
Fix harmless compiler warning.