Merge nas2d-tests repository

[DanRStevens]

The nas2d-tests repository should be merged with the main nas2d-core repository.

Merging will make it easier to keep the test projects up to date with the main library project. It will also encourage more testing, as it will be easier to do.

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As these tests are not automated, perhaps we can put them in a sampleProjects/ folder.

To that end, we'll probably want to rename them from "test_1" etc., and give them more descriptive names, based on what features they are exercising. The new test-graphics/ project can be placed in a similar folder.

Suggested layout:

sampleProjects/
  zombieGame/  (test_1)
  rendererFunctions/  (test_2)
  blendingModes/  (test_3)
  texturing/  (test-graphics)

I would welcome suggestions for better names.

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I noticed there is a fair bit of similarity between test_2 and test-graphics. Should these two be combined? I imagine they weren't since test_2 was quite dated for a while, and didn't compile with recent versions of NAS2D. Now that it's been updated though, would it make sense to merge them?

[ldicker83]

Was going to say, these are probably better labeled 'sample apps' versus tests. I mean, there's the 'renderer test' which I sort of use for testing some renderer functions but it's also a good demonstration of the various features of the renderer.

Then there's the others which are literally just sample apps demoing different parts of the framework, etc. plus a sample game that I think can be better fleshed out. Doesn't have to be more complex than it already is (just add a sort of 'waves' mechanic and have zombies show up in different patterns, fix the way they disappear, etc.)... anyway, I'm getting into a different changeset and topic at this point.

[DanRStevens]

Actually, now that you mention it, it might make sense to separate out the zombie game into it's own repository, and keep the others as sample apps. That would also minimize the asset references by the sample apps, since the zombie game is responsible for most of the asset references.