Adds -= operator
An elementwise -= operator is added to the autodiff class.
Adds new well formulation
Todo: incorporate WellDensitySegment. Currently values of the pressure
drop is hardcoded to make the rest of the code work
Todo: make it possible to shut perforation with crossflow.
fix the fallout of the SimulatorTimer::currentTime() -> SimulatorTimer::simulationTimeElapsed() rename
go back to incrementing the current simulation time first, then calling EclipseWriter::writeSolution()

for this not to trigger an assertation after the last time step, the
changes of OPM/opm-parser#141 are required.
Merge remote-tracking branch 'totto82/new_well_formulation' into new_well_formulation
Whitespace fix.
Minor whitespace adjustments.
Work in progress: use WellDensitySegmented class.

This is work in progress since it is non-working: phaseRates() is
not used correctly, and changes must be made to WellState or equivalent.
Merge pull request #97 from andlaus/fix_simtimer_rename_fallout

fix the fallout of the SimulatorTimer::currentTime() -> SimulatorTimer::simulationTimeElapsed() rename
Add WellStateFullyImplicitBlackoil class.

This is intended to be used instead of the WellState class in the fully
implicit blackoil simulator. It contains a WellState to reuse the init()
method and to enable users to call functions requiring a WellState.
This is done with containment and an access member function,
basicWellState(), instead of with inheritance to minimize surprises.
Use WellStateFullyImplicitBlackoil class instead of WellState.
Merge pull request #102 from atgeirr/separate-wellstate

Specialized well state class for the fully implicit blackoil solver.
sim_fibo_ad: convert to the new-style wells manager

i.e. it now uses Opm::EclipseState. This change required to re-add the
the epoch concept in some sense, but the loop variables now call it
"episode" which sounds less ethernal IMO.
sim_fibo_ad: fix writing

the initial condition was written multiple times. We now fix this by
not writing anything in the simulator and moving this logic to the
main loop..
Merge pull request #98 from andlaus/reverse_increment_write_order_again

go back to incrementing the current simulation time first, then calling EclipseWriter::writeSolution()
Merge pull request #101 from andlaus/sim_fibo_ad_use_new_wellmanager

sim_fibo_ad: convert to the new-style wells manager
Merge branch 'master' into new_well_formulation

Conflicts:
	opm/autodiff/FullyImplicitBlackoilSolver.cpp

To resolve conflicts, WellState was changed to WellStateFullyImplicitBlackoil
in multiple places, and perfRate() changed to perfPhaseRate() in
WellDensitySegmented.
sim_fibo_ad: re-add ouputting of the current report step when using opm-parser

in the old parser, this was called 'epoch'...
sim_fibo_ad: don't instantiate an old parser object if USE_NEW_PARSER is set anymore

I thought I included this in a previous PR. Seems like I was wrong...
Merge pull request #104 from andlaus/sim_fibo_ad_print_reportstep

sim_fibo_ad: re-add ouputting of the current report step when using opm-parser