fix: wsba plugin settings display to all each plugin

Firsrt release to WordPress.org.

Fix code for WordPress Plugin Review (Sanitize, Validation, Escape and delete Unneeded Folders) and minor change.

• Sanitize every input from submit form.
• Validate every input from submit form.
• Escapce every output in DB.
• Delete Unneeded folders(ex: tests and docs).
• Use thirdparty validation library(Valitron).
• Add settings link in WP Admin Plugin page.
• Refactoring entire code.

Submit first version to WordPress.