Adding simple full build of both Debug and Release using global scripts

Removing mono subset from builds

Adding UTF8String OOB package to the build

Adding post-Build extensibility in order to create artifacts out of
build output for coreclr and libraries tests.

Addressing PR Feedback

Adding libraries tests and coreclr test build

Fixing test execution for libraries and coreclr test build

Adding CoreCLR test execution

Addressing PR Feedback

Fix Coreclr Test run by adding test native assets artifact

Add build of native coreclr test assets

Fixing path of coreclr native test assets that are published

Fixing dependsOn for coreclr Windows tests