datetime improvements and unit tests
PackageLoader.TryLoadFrom and ReflectionOnlyTryLoadFrom - helper methods to support safely loading managed assemblies
Clean up comments
Merge remote-tracking branch 'upstream/master' into PMBinaries
Merge branch 'SolarRadiation' of https://github.com/DynamoDS/Dynamo into sunsettings
added unit tests for sunsettings
Merge remote-tracking branch 'origin/master' into SolarRadiation
Merge pull request #2809 from pboyer/PMBinaries

Special checks to prevent loading un-managed assemblies in Package Manager
Merge branch 'master' of https://github.com/DynamoDS/Dynamo into Revit2015
Merge pull request #2830 from Benglin/Revit2015

Cross merging master changes into Revit 2015
Merge remote-tracking branch 'origin/master' into SolarRadiation

Conflicts:
	src/DynamoCore/PackageManager/Package.cs
Merge remote-tracking branch 'origin/SolarRadiation' into SolarRadiation2015
Merge remote-tracking branch 'origin/Revit2015' into SolarRadiation2015