Fixed memory leak in Collection class with a new implementation.

#478 - memory consumption optimized from 12,377,160 bytes to 6,053,976.
Merge pull request #482 from marcj/perf2

Fixed memory leak in Collection class with a new implementation.
add compatible doCount and doSelect methods from query_cache behavior
with ModelCriteria class

return DataFetcherInterface instance for doCount and doSelect methods in
query_cache behavior
Merge pull request #484 from lunika/master

fix query_cache behavior compatibility with Criteria and ModelCriteria
Fixed notice
Merge pull request #494 from marcj/patch-1

Fixed notice
Tables with no primary keys confused code generators
must test if setIgnoreCase exists on each criterion
fix failing tests in ArrayToPhpConverterTest
Merge pull request #506 from csanquer/master

fix failing tests in ArrayToPhpConverterTest
Added hhvm to travis config
Merge pull request #507 from staabm/patch-1

Added hhvm to travis config
Merge pull request #505 from lunika/getParamsIssue

must test if setIgnoreCase exists on each criterion
Merge pull request #504 from K-Phoen/fix-452

Fix #452
Fixes #508
Merge pull request #510 from gossi/master

Add DataFetcherInterface for generated Map Classes. Fixes #508
fix array casting in InCriterion and InModelCriterion. Fix #492
Merge pull request #512 from lunika/InCriterionFix

fix array casting in InCriterion and InModelCriterion. Fix #492
Fixed missing closing "database" tag.
Fixed #520, related to #452