Merge branch 'marta-branch' of github.com:cdanielmachado/framed
Merge branch 'master' of github.com:cdanielmachado/framed
Fixed a couple of problems in GlpkSolver
Tried to fix a couple of things in GlpkSolver
fixed glpk row bounds + status mapping

if row lb == ub: the bound is fixed, otherwise it is a double bound;
the glpk status mapping is now completed and both statuses INFEASIBLE
and NOFEASIBLE are mapped into INFEASIBLE
reset objective function after solving the problem
fixed loop that goes through all the objective function coefs
presolve is back
Merge branch 'fix_glpk'