Feature/simple test cases

Add a few simple examples, that can also be used as test cases of "full" programs.

This should test quite a few cases for all methods.

Current important cases to consider:

• 1) Staggered: 1d static system must obey minimum domain size constraint
• 2) Staggered: 1d system, which shrinks, but must obey minimum domain size constraint (will fail at the moment)
• 3) Staggered: same as 1), but from Fortran to show that interface as well.

1. is given in ALL_Staggered.cpp already.

Also todo is to create a way to check the tests for validity. The proposal here is to generate a known good output and commit that. Then run the example and compare its output with the known good solution. For this we need a method to compare (with a certain degree of leeway to account for floating point rounding) the two sets of data. This shold not be difficult to code, once the output format is decided upon.