Managed under GitHub Discussion #3317

Replace all literal strings associated with Settings object.
String literals replaced with const std::string variables ensuring accuracy.

Correct mispelled or incorrectly called Settings::IsVaildSettings with correction.
(Vaild --> Valid)

Remove variable shadowing in Settings::IsValidSettings and ::setUserSettingsFile.

Ensure clarity/rename variable names to reflect INI definitions ([section]key = value)

Managed under GitHub Discussion #3317

Establish default settings access mechanism and values.
This include establishing default font value.
Execution of settings object was reworked.

Managed under GitHub Discussion #3317

Mechanism implemented to replace deprecated or bad section/key pairs that may
exist in user's settings file. Also, another mechanism is implemented to remove
bad section/key pairs that DO NOT have a replacement and are no longer used.

Managed under GitHub Discussion #3317

Rework mechanism to initialize settings object.
Effort made to improve settings file handling on start up.