Bug fixing
adding massflowrate objective fnct adjoint. also changing freestream sensitivity to include inlets
mass flow rate objective function adjoint
Revert "Mass flow rate and supersonic inlet adjoint bc's (euler)"
added config options group to doxygen

In adjoint subsonic outlet bc: direct soln values using Reimann and c instead of c^2
added inlet conditions to farfield sensitivity calcs
added config options group to doxygen
 massflowrate added as output; added to history file if obj fun is massflow
added CEULERADJ supersonic inlet BC
Merge remote-tracking branch 'upstream/develop' into upstream_dev