CRA-568: Set up old background model (multizone and generate) to work with CommonData. Does not compile.
CRA-568. Added SetupBackgroundModel. Currently missing is writeBackground and if multiinterval is used with background given by file.
Merge pull request #36 from enesvold/CRA-505

#CRA-577, #CRA-574
CRA-568: Updated SetupBackgroundModel.
CRA-505: Merge with enesvold.
CRA-505, CRA-561, CRA-579: Fixed some bugs after testing. Made more consistent error-handling in CommonData.
CRA-539, CRA-533, CRA-568: Small fixes after testing.
CRA-581: Set up TimeLine in CommonData
CRA-505, CRA-579, CRA-581: Cleanup and small fixes with error handling.
Merge pull request #37 from hgolsen/CRA-505

Cra 505, CRA 568
CRA-568: Cleanup/warnings.
CRA-585: Copied functions for ModelGravityStatic and ModelGravityDynamic with GravityInversion from veralh.
CRA-585, CRA-587: Added updated gravimetric files from veralh.
CRA-585: Added data for Gravity in CommonData. Created new constructors for ModelGravityStatic and ModelGravityDynamic.
CRA-587: Set up data for TravelTime in CommonData from TravelTimeDynamic.
CRA-527, CRA-531, CRA-553, CRA-590: Fixed facies_names from well-logs, added eroded surfaces to simboxes.
CRA-584, CRA-593: Started on priormodel 3D. Started on replacing fftgrid to NRLib::Grid in ReadGridFromFile.
CRA-581, CRA-585, CRA-593. Added changes for Gravimetric. Added the new resample algorithm to CommonData, with NRLib Grid as input.
CRA-561, CRA-593: Fixed Prior Facies Cubes for multiple intervals. Added intervals to ReadGridFromFile.
CRA-559: Fixed trend-cubes, replaced FFTGrid with Grid.