Merge branch 'adf' into publicdev
Merge pull request #482 from yitao-zhang/merge

Sync with the latest bits from azure-sdk-tools/dev branch
Added DataFactory cmdlets and test project.
Downgraded xunit to 1.9.2 for ADF test project.
Added new Target for running Azure DataFactory tests.
Added Http mock recording for ADF.
Added Unit tests for ADF Get-AzureDataFactory cmdlet and refactored folder sturcutre.
Added Help.xml file for DataFactories.
Added Hydra nuget feed into build.proj of adf branch.
Updated adf branch's build.proj with Hydra Nuget feed and fixed Internal visible issue for adf test project.
Add adf tests into Pull request checkin tests list.
Copy ADF Http mock test session records for checkin test.
Clean up ADF codes to address PR comments.
Updated ADF MAML Nuget to base on WindowsAzure.Common 1.3.0.
Added ADF dlls into MSI.
put back Version in the PaaS set cmdlet
Merge pull request #1 from Azure/adf

Adf
Used DataFactoryFilterOptions for Get and List and removed IDataFactoryClient interface for better Moq mocking.
Minor text changes in unit tests.
Removed DataFactory properties for now.