* Add prelimianry support for extensions to Razor
This PR adds MSBuild insfrastructure to the SDK that can understand
concepts we need to expose to the project, code generator and runtime
like:
- Language version
- Configuration
- Extensions (plugins)
As an example of how this works, I've done the wireup for MVC. This will
now generate assembly attributes in your application that can act as a
source-of-truth for what should be included in runtime compilation, and
it's all based on the project-file. This means that it can be delivered
and configured by packages.
The next step here is to implement a loader for RazorProjectEngine based
on these primitives, and then use it in our CLI tools and MVC.
The next step after that is to expose it in VS and VS4Mac through the
project system.
* Add metadata to Razor
This PR introduces standard metadata to Razor. This change begins to
formalize the contract between generated code produced by Razor and
runtimes that want to load and interact with this code.
This is a step on making MVC a 'plugin' to Razor rather than the only
possible implementation. Since we're doing MSBuild work - this is the
right time to designate the current interaction between Razor and MVC as
'legacy' and move forward.
Additionally, we need the source thumbprinting to make re-compilation of
Razor a thing.
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Also I noticed that our source document doesn't expose the hash
algorithm by name. We really should have this, so I added it and
hardened the code that deals with checksums in c# generation.
Pranav K
Ryan Nowak