ERT-753: Added bool mount option to enkf_fs_create()
ERT-753: Added class run_arg

The run_arg class is as imple value object designed to hold on to the
information needed to run one realisation. The run_arg objects should
not be reused for additional simulations.
ERT-753: Added ert_run_context class

The ert_run_context class holds on to all information needed to run one
simulation.
ERT-753: Removed stale runpath test
ERT-753: Compltede run_type enum in Python
ERT-753: runpath_list owns the output filename.
ERT-753: Removed stale functions from EnkfState
ERT-753: Added __contains__() + getNode() to EnkFState
ERT-755: Added getRealisation() to EnkFMain
ERT-753: ErtSocket will include traceback in error.
ERT-753: Changed status: OPEN -> READY
ERT-753: Added function to run/parse cmdfile
ERT-753: Start simulation from EnkFMain
ERT-753: Server & client updates
ERT-753: Using run_arg in enkf_state
ERT-753: Using ert_run_context in enkf_main

This is a large - "the rest" - commit containing many partly unrelated
changes. The main change in this commit is that enkf_main and all
running of simulations is based on the run_arg and ert_run_context data
types.
ERT-753: Fixed several tests to use run_context
ERT-753: Minor const beautification
ERT-755: Changed basecclass to check for None

Have changed the basecclass class methods createCReference and
createCObject to compare input c_pointer with None instead of numerical
0.