Updates from PR#127 from Lars-Erik. Had to manually copy in the changes because the PR was closed.

Adds Import of Dictionary Items to the PackagingService along with tests and a fix for the DictionaryRepository.
Adding Export of DictionaryItems including test
Adding languages xml to existing xml file for testing purposes
Moving events out of the repository scope.

Adding Get Language by Iso Code method
Adds import and export of languages along with tests
Removing some internal experimental stuff that isnt used
Updating a few methods that are made public in 7.0.2
Updating the legacy Installer class to use the new methods in the PackagingService
Updates from PR#127 from Lars-Erik. Had to manually copy in the changes because the PR was closed.

Adds Import of Dictionary Items to the PackagingService along with tests and a fix for the DictionaryRepository.

Conflicts:
	src/Umbraco.Tests/Services/Importing/ImportResources.resx
	src/Umbraco.Tests/Services/Importing/PackageImportTests.cs
	src/umbraco.cms/businesslogic/Packager/Installer.cs
Adding Export of DictionaryItems including test

Conflicts:
	src/Umbraco.Core/Services/PackagingService.cs
	src/Umbraco.Tests/Services/PackagingServiceTests.cs
Adding languages xml to existing xml file for testing purposes
Moving events out of the repository scope.

Adding Get Language by Iso Code method
Adds import and export of languages along with tests

Conflicts:
	src/Umbraco.Tests/Services/PackagingServiceTests.cs
Removing some internal experimental stuff that isnt used
Updating the legacy Installer class to use the new methods in the PackagingService

Conflicts:
	src/Umbraco.Core/Services/PackagingService.cs
	src/umbraco.cms/businesslogic/Packager/Installer.cs
Fixing merge issue
Adding new methods to the IPackagingService interface
Adding event handlers to new import and export methods in the PackagingService
Completed new NotificationService, moved Diff to Core
Moves all notification sending logic to the notification service, improves performance during any action when notifications are to be sent, ensures emails are sent out async to not block up the current request.