Make Modules.Cache thread safe
Parallel and Async Build() for NoiseMaps

Note: callback is not supported for parallel and async builds.
Merged in tombah/sharpnoise/parallel (pull request #1)

Parallel NoiseMapBuilders
Show the time it takes to generate the planet surface in ComplexPlanetExample
README.md edited online with Bitbucket
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README.md edited online with Bitbucket
README.md edited online with Bitbucket
README.md edited online with Bitbucket
README.md edited online with Bitbucket
Use cancellation token in Cylinder and Plane NoiseMapBuilders
Add documentation for the new Build methods
Remove the old NoiseMapBuilder.Build method, and rename the BuildParallel methods to Build

The progress callback is also removed for now.
Remove useless Task use from planet generator
PlanetExample: add a progress dialog (with just a cancel button for now), and the related support code
Fix reset of Cache Module.

Setting the localCacheEntry.Value to null only clears the value for the executing threads ,not all threads. So create a new ThreadLocal instance instead.
Explicit Clamp() implementaions for int and double. This is considerably faster than the generic version.
Use System.Math Min() and Max() instead of custom versions. The system versions are faster than the custom version using generics.
Remove Min and Max tests from NoiseMathTests, as we now use the System.Math versions
Fix comment on Map.Clear(). The runtime always zeroes allocated arrays.