Remove remaining SETERRQ macros. Compiles.
OptionsList and set_config_from_options don't need an MPI_Comm.
Use more exceptions in columnSystemCtx.
Overhauling columnSystemCtx and friends

(the I/O and error handling parts).

Now columnSystemCtx does not use error codes (throws exceptions instead)
and we use C++ STL fstream to save .m files.

columnSystemCtx does not depend on PETSc any more.