Fidget

Added
* tabs can now handle arrow keys to switch tabs
Fixed
* `FidgetConfirm` without a cancel value would return garbage if closed
Changed
* Major Code refactoring in `widgets`, including:
* Common superclass to `FidgetDict`, `FidgetTabs`, and `FidgetTuple`
* Split `FidgetLabel` to two classes: `FidgetConst` for immutable values, and `FidgetLabel` for mutable
* common superclass to `FidgetCheckBox, FidgetComboBox`, `FidgetRadio`, `FidgetDiscreteSpinner`, and `FidgetConst`
* common superclass to `FidgetLine`, `FidgetPlainText`, `FidgetEditCombo`, and `FidgetLabel`
* common superclass to `FidgetMatrix`, `FidgetTable`
* If a `FidgetConfirm` does not have a cancel value, its close button will be disabled.
* `FidgetFilePath`'s glob parser was changed to explicit
Removed
* got rid of `FidgetImagePath`, it will be reintroduced as a more generic preview wrapper.

Added
* FidgetSpin has initial value parameter
* Parsers and printers can now be prioritized with the `low_priority`, `high_priority`, `mid_priority` decorators
* added the `FidgetTabs` aggregate
* FidgetCombo's options is now a dual parameter
Changed
* errors on arguments not provided now also include self
* the name and fields of namedtuple type of FidgetTable and FidgetTuple is now automatically adjusted to an identifier.
* fidget now uses its own embedded icons, courtesy of [feather](https://feathericons.com/).
Fixed
* error when setting initial value for minimal
* minimal dialog will have correct parent
* optional plaintext printer misbehaving
* FidgetCombo's parse can now handle any printed value

Added
* Initial release