Allow empty string in flag values

Defuault suggest true/false for bool flags

tab completion fixes

Much better zsh tab completion; package/type re-org

scalar.PointerTo and bash zsh tab completion

Standardize opt function names

Remove `WARG_PRE_V0_0_26_PARSE_ALGORITHM`

Parse update! Flags must be passed after commands

Update values, use path.Path

Remove section flags in favor of app global flags