Merge pull request #3285 from junmendoza/Revit2015

Cross merge to Revit2015
Code block node formatting fixes
updated comment
Fix failing test cases
Changes according to comments
Add ProtoTestBase to handle common SetUp and TearDown event
Check null before cleaning test core
Inherit test from ProtoTestBase
Inherit test from ProtoTestBase
Rename variables to avoid confusion
Merge pull request #3292 from Randy-Ma/fix_failing_test_cases

Fix failing test cases because some entities are still in use after disposed
Recommit some files
Fix failing test cases
Fix build error
Changes according to comments
Rename variables to avoid confusion
Dispose liverruner in the test
Merge pull request #3296 from Randy-Ma/master

Pick commits from the Revit2015 branch to the master branch
Clear dependencies of a redefined graphnode only after determining the redefinitions

1. Cleanup function
2. Move dependency redefining at a later step
Use FFITarget.dll for import testing