code opt further

[jarjk]

• misc: all error msg lowercase
• feat(utils): get clean program name
• misc(meson) don't build the static lib, simpler for now
• BROKEN misc(Arg): better private member names
• BROKEN feat(Arg): getters and setters a A LOT better + more usable
• BROKEN misc(Arg): better nameing in source file
• BROKEN fix(Arg): adjust '<<' overload for new privates
• BROKEN fix(Arg): removed old getter/setter defs
• BROKEN fix(Arg): remove unneeded redeclaration
• BROKEN misc(Arg): use more explicit names again and even more
• BROKEN fix(Arg): reworked the constructor
• BROKEN fix(Arg): clean up includes
• BROKEN feat(utils): move src/utils.cpp -> include/utils.hpp
• BROKEN fix: cleaned all includes in all files
• BROKEN misc(Parser): added a const ref, removed unneeded
• BROKEN fix(Parser): using new arg getters/setters, we gettin' there!
• fix(Parser): switch to PROGRAM_NAME() util, all fixes done maybe?
• misc(Arg): rename try_env -> auto_env
• feat(example): WIP added example
• refactor(parser): add this where possible
• fix(parser): know what's static and what's const

[csboo]

As always thx for contributing the project!
I'm closing this pull because most of these changes have either been merged, or the code regarding them has completely been refactored, for further information see: #17

[jarjk]

good.