Template debugging

Add the ability to debug templates (merged from 83ae2e2). The commit is mostly about passing the templatefilename to the razor generator. In case of compile time errors the filenames are present in the CompilerErrorCollection which is very helpful.
If debugging is enabled the compiler will generate #line pragma's. As a result razor templates are debuggable in visual studio. Debugging is disabled by default, but it is easy to enable:
```c#
var config = new TemplateServiceConfiguration();
config.Debug = true;
Razor.SetTemplateService(svc);
```

The other commit extends IAngularResolver with a ResolveFilename() method. This allows embedded resources or templates in the database to be debugged, as long as there is a copy on the filesystem.