new array refs: accept signatures with assignable to int params (IDEA-106973)
mismatched collections: method references check (IDEA-107001)
no need in additional lib
IDEA-107072 Breakpoint dialog: usability problems and other bug
Code style fixed  in HG tests.

*File name variables removed from HgPlatformTest (use local ones in appropriate methods);
* HgMergeProvider filed moved from HgPlatformTest to HgMergeProviderTest;
*Second repository creation moved to test methods;
*UpdateProject  method added  to HgExecutor;
*Unnecessary comments removed from MergeProveder tests.