Document common definitions

[vitaut]

The documentation at http://ampl.github.io/common.html needs to be completed.

[vitaut]

Need to do something about \rst/\endrst first as they add to much noise.

[vitaut]

Also using :cpp:any: with defaultrole should make references much shorter.

[vitaut]

What needs to be documented:

mp/nl.h:86: warning: Compound mp::BinaryReadError is not documented.
mp/nl.h:68: warning: Compound mp::ReadError is not documented.
mp/common.h:396: warning: Compound mp::expr::OpCodeInfo is not documented.
mp/nl.h:233: warning: Member operator<<(fmt::Writer &w, const NLHeader &h) (function) of namespace mp is not documented.
mp/common.h:687: warning: Member num_common_exprs_in_both (variable) of class mp::ProblemInfo is not documented.
mp/common.h:688: warning: Member num_common_exprs_in_cons (variable) of class mp::ProblemInfo is not documented.
mp/common.h:689: warning: Member num_common_exprs_in_objs (variable) of class mp::ProblemInfo is not documented.
mp/nl.h:75: warning: Member ReadError(fmt::StringRef filename, int line, int column, fmt::StringRef message) (function) of class mp::ReadError is not documented.
mp/nl.h:80: warning: Member filename() const  (function) of class mp::ReadError is not documented.
mp/nl.h:81: warning: Member line() const  (function) of class mp::ReadError is not documented.
mp/nl.h:82: warning: Member column() const  (function) of class mp::ReadError is not documented.
mp/nl.h:92: warning: Member BinaryReadError(fmt::StringRef filename, std::size_t offset, fmt::StringRef message) (function) of class mp::BinaryReadError is not documented.
mp/nl.h:97: warning: Member filename() const  (function) of class mp::BinaryReadError is not documented.
mp/nl.h:98: warning: Member offset() const  (function) of class mp::BinaryReadError is not documented.
mp/common.h:687: warning: Member num_common_exprs_in_both (variable) of class mp::ProblemInfo is not documented.
mp/common.h:688: warning: Member num_common_exprs_in_cons (variable) of class mp::ProblemInfo is not documented.
mp/common.h:689: warning: Member num_common_exprs_in_objs (variable) of class mp::ProblemInfo is not documented.
mp/common.h:407: warning: Member GetOpCodeInfo(int opcode) (function) of namespace mp::expr is not documented.
mp/common.h:412: warning: Member opcode(expr::Kind kind) (function) of namespace mp::expr is not documented.
mp/common.h:418: warning: Member str(expr::Kind kind) (function) of namespace mp::expr is not documented.
mp/common.h:401: warning: Member kind (variable) of class mp::expr::OpCodeInfo is not documented.
mp/common.h:402: warning: Member first_kind (variable) of class mp::expr::OpCodeInfo is not documented.
mp/common.h:404: warning: Member GetOpCodeInfo(int opcode) (friend) of class mp::expr::OpCodeInfo is not documented.

[vitaut]

Remaining warnings:

common.h:656: warning: Compound mp::expr::OpCodeInfo is not documented.
common.h:40: warning: Member GetOpCodeInfo(int opcode) (function) of namespace mp::expr is not documented.
common.h:40: warning: Member opcode(expr::Kind kind) (function) of namespace mp::expr is not documented.
common.h:656: warning: Member kind (variable) of class mp::expr::OpCodeInfo is not documented.
common.h:656: warning: Member first_kind (variable) of class mp::expr::OpCodeInfo is not documented.
common.h:656: warning: Member GetOpCodeInfo(int opcode) (friend) of class mp::expr::OpCodeInfo is not documented.

[vitaut]

All expression kinds are documented as of fd16dd5.