Add TileFeature Type

[jamesmcclain]

In this pull request the TileFeature[T, D] type is added.

Points to Examine

• The TileFeature[T <: CellGrid,D: ? => BundleMethods[D]] type takes two type parameters, but the merge methods (in both raster and spark assume that T <: Tile. There are no assumptions on D other than it being a member of the bundle type class.
• There is a question of range and precision of the data D. Right now they are treated as integer entities. Double versions are possible as well, but since one of the supported types of D is Seq[Tile], there is a question of how (best) to handle the situation when the data are mixed integers and floats.
• I found that I had to add these secondary conversions from subclasses of BundleMethods[D] to BundleMethods[D] in order to get the constraints on TileFeatureMergeMethods to be satisfied. The issue seems to be that the Scala compiler does not look more than one layer deep when trying to satisfy these constraints. If there is a better way to handle this, I am open to it.

Still Need To

• Provide Bundle Methods for Seq[Tile]
• Provide Appropriate I/O support for TileFeatures
• Provide Merge Methods for RDDs of TileFeatures
• Move bundle methods to their own directory
• Write ScalaDocs
• Integrate Tests into PersistenceSpec

[lossyrob]

FunSpec, should be named Spec instead of Tests. Tests represents FunSuite tests.

[jamesmcclain]

I named this one after the file .../spark/io/LayerUpdateSpaceTimeTests.scala from which it was copied (same is true for .../spark/io/CoordinateSpaceTimeTileFeatureTests.scala and .../spark/io/AllOnesTestTileFeatureTests.scala). I can change the names of one or both of these sets of tests, if desired.

[lossyrob]

+1 after comments addressed

[jamesmcclain]

All comments have been addressed with the exception of the LayerUpdateSpaceTimeTileFeatureTests.scala naming issue which is discussed above.

[jamesmcclain]

All comments have been addressed with the exception of the LayerUpdateSpaceTimeTileFeatureTests.scala naming issue which is discussed above.

Just to amplify, I am curious to know whether I should just change the names of the files that I added, or also change the name sof the files that they are based on.

[lossyrob]

The latter choice, change all the incorrect ones. Thanks.

[jamesmcclain]

Okay, will-do.

[jamesmcclain]

All comments prior to this one have been addressed.