Minor improvements in build and test system.

- ignore *.orig
- *.tst rules in tests directories; to run only one con file
- commented recepie to coberture usage (cover testst)

Conflicts:
	unit_tests/system/tokenizer_test.cpp
More specific subtests of test 20.

covered:
- old adsorption code
- new code using tables
- new code with spatialy variable param, use non-lin solver
  directly
- all three isotherms

missing: limited solubility, concentration out of table
Optimization and polishing of isotherm.*

- remove unnecessary stuff
- some inlining to narrow critical code points
- improved class documentation
- necessary changes in sorption.cc and transport.cc
Commit before pull from master.
Merge branch 'LZ_interface' of https://github.com/flow123d/flow123d into LZ_interface
Needed to enable pull changes from origin.
Classes derived from SorptionBase, compilable code.
1 error in 1 context reported by valgrind.
Some comments either added or removed.
Assert added to field_base_impl.hh .
Add setters in Reaction class.

- add method for setting mesh and names of substances.
Add setting TimeGovernor.

- add setter of TimeGovernor.
- setting time in transport operator splitting.
Add init_from_input method to Reaction.

- add inherited methods to all ancestors.
- remove prepare_inputs methods (move code to init_from_input).
Set Time Governor of Sorption.

- set time of Sorption data
Add EquationBase.set_concentration_vector method.

- prepare empty method of descendants.
Remove Reaction.compute_one_step method.

- remove method in all descendants
- replace the update_solution method
Add Reaction.get_element_for_dof_index method.

- method finds mesh elemnt for local dof index.
Merge with 'DF_reaction_interface', compiles, test20 not working.
Fixed merge with DF_interface - test20 running.

- set_time_governor method added in EquationBase
- dual porosity and sorption dual switched off sofar
Remove set_time_step methods from reactions, clean reaction classes.

- remove set_time_step, use given time_governor data instead
- clean unused methods from reaction classes
Clear rest of set_time_step methods.

- cleared rest of set_time_step methods in linear reaction and pade approximant
- cleaned a little the mess among virtual methods in linear reaction and pade approximant
Array of species  moved to Reaction record.

- move record for array of species to abstract reaction class
- mapping from local indices of substances to their global indices done in abstract reaction class
- clear a bit the reaction and sorption classes