FileFormats.MPS: support QUADRATIC

[odow]

MOSEK

https://docs.mosek.com/7.1/capi/The_MPS_file_format.html

QSECTION

Gurobi

https://www.gurobi.com/documentation/9.1/refman/mps_format.html

QUADOBJ

QCMATRIX

CPLEX

https://www.ibm.com/docs/en/icos/20.1.0?topic=extensions-quadratic-objective-information-in-mps-files
https://www.ibm.com/docs/en/icos/20.1.0?topic=extensions-quadratically-constrained-programs-qcp-in-mps-files

QMATRIX

QCMATRIX