basic pyfield tests
solver parameters tests
Merge remote-tracking branch 'mach/master'
Merge remote-tracking branch 'mach/master'

Conflicts:
	resources/test/script/field.py
	resources/test/script/problem.py
minor improvement of preprocessor
fixed derivative in Richards
fix
Merge remote-tracking branch 'kus/master'
Picard's solver for Richards
added missing files
fix in problem dialog
minor fix in problem dialog
small fix in pyfield
wrapper for order component added
pyproblem testing finished