rebasing to upstream/develop
In adjoint subsonic outlet bc: direct soln values using Reimann and c instead of c^2
more doxygen comments added
 addtl correction to psi_outlet[0] and addition of mass_flow_rate objective term to psi_outlet[0]
fixed typo
more doxygen comments added
added config options group to doxygen
more doxygen comments added
added config options group to doxygen
more doxygen comments added
fixed typo
mass flow adjoint (euler) ready for testing
added inlet conditions to farfield sensitivity calcs
 massflowrate added as output; added to history file if obj fun is massflow
bug (not sure if should be committed for real) in projection
undid previous projection change, added massflowrate to su2_dot output
fixing commit issue
translated a comment from spanish to english
slight change to mdot
added config options group to doxygen