Adjoint new try

[hnil]

Merged the old pull request into master. It compile and seems to run all tests. Parallel testing not done. This facilitate the adjoint work. A more general approach than focusTimeIdx index will facilitate sequential solves with minimal change to the core of the simulator. (This will be left to after the adjoint is merged).

This will be followed by pullrequest in opm-simulator and opm-tests