Initial configuration changes
- Flow configuration everywhere target fraemwork flows (except dependency
walking)
- Added ChangeConfiguration command to design time host
- Added ProjectConfigurations and Frameworks to the project info message
in design time host. The reason it's called project configurations is so that
we don't break current versions of VS.
- Added Configuration to IApplicationEnvironment
- Support "frameworks" node in project.json that will contain target frameworks
- Added default compiler options for debug/release
- Skip configurations that are target frameworks
- Combine options from root, configuration and target framework.
- Added Combine to CompilerOptions that combines a list of
 CompilerOptions in order applying them left to right.
- Made boolean CompilerOptions nullable so we can detect if they were
 set of not.
- Always have default target framework specific compiler options.
- Build packages per configuration.
More configuration changes
- Added tests for combining CompilerOptions
- Updated unit tests and klr.cmd
- Move default configuration list to BuildManager
- Fixed the makefile.shade
- Change to debug configuration