refactor option handling (#1351)

refactor option handling (#1351)

* rough in Option class

* testo passes

* rough in OptionBool

* more OptionBool use

* more OptionBool

* fix isEmpty

* store qstrings

* dont return const

* rename

* convert a few lost ARGTYPE_BOOLs to OptionBool.

* utilize avalable QString for options.

* obsolete argvalptr

* Option is abstract class

* eliminate special handling of ARGTYPE_BOOL without default in vecs.

* fix #982 ...

garmin, ozi, xcsv mkshort options whitespace_ok, must_unique broken since 2006.

* test to make sure OptionBool iff ARGTYPE_BOOL

* use OptionBool for all ARGTYPE_BOOL options.

* correct OptionBool type.

* delete unused parameterized Option ctors.

* format and comment option.h

* nodiscard for class Option.

* vecs nullptr checks

* have Vecs::validate_args check argval isn't nullptr.

* catch up includes

* clarify comment

* fix introduced bug caught by tidy.