Add Microsoft.Data.Entity.Build.Tasks

[bricelam]

@bricelam seven years ago:
We don't need to open source that. It never changes and will always ship as part of .NET Framework.

@bricelam seven years later:
Crap. We need it on .NET Core.

Changes to the original code:

• Updated file headers
• Renamed BuildTasksResources.resx to Properties/Resources.resx
• Removed unused XmlConstants members
• Simplified EntityDesignerUtils by inlining some constants

Fixes #828

[bricelam]

@natemcmaster @pranavkm Any gotchas implementing a cross-platform MSBuild task or using NuGet's buildTransitive directory?

[pranavkm]

@javiercn used the buildTransitive feature recently with build targets, he might know more.

[javiercn]

AFAIK it works just fine.

[javiercn]

The way we build packages is we create three folders and have buildTransitive point to buildMultitargetting and that one point to build

[bricelam]

Oh interesting. Presumably for compatibility with different NuGet clients? I think this one is TFM-specific so buildCrosstargeting may not make sense, but build might.

[bricelam]

Yeah, i think I’ll add a build directory. This would enable net40 projects building with older NuGet clients.

[natemcmaster]

@javiercn's suggestion is a good one. Only one of the build*/ folder conventions is used at a time. I've adopted the practice of only shipping one copy of the "real" props and targets which understand the MSbuild context they are in (inner or outer build), and then adding several dummy targets which match the various NuGet conventions, build/, buildMultiTargeting/, buildTransitive/, sdk/, etc.

Another gotcha is that there is no way to make buildMultiTargeting/, but since it doesn't appear you need to import props/targets in the outer build of a multi-targeting app, you're okay on this one.

/cc @jainaashish in case he is aware of any other gotchas with buildTransitive/

[bricelam]

Updated in #894