* CredentialService initial impl with Win32 support
- Basic CredentialService APIs for Save, Read, Delete
- E2E unit tests for Credential Service
- Win32 implementation with unit tests
* Save Password support on Mac v1
- Basic keychain support on Mac using Interop with the KeyChain APIs
- All but 1 unit test passing. This will pass once API is changed, but checking this in with the existing API so that if we decide to alter behavior, we have a reference point.
* Remove Username from Credentials API
- Removed Username option from Credentials as this caused conflicting behavior on Mac vs Windows
* Cleanup Using Statements and add Copyright
* Linux CredentialStore Prototype
* Linux credential store support
- Full support for Linux credential store with tests
* Plumbed CredentialService into Program init
* Addressing Pull Request comments
