Ability user search quotes - #19

This ticket was to add in the ability for the user to search for a quote by author or by quote

Changes made

• Added in a UserInputValidator file to clean the data to ensure it can be searched on, and send it to the database query function
• Added in a test_UserInputValidator file to test the regex
• tab1 changes:
  • created two separate search boxes to allow users to search by author or quote
  • created a function to get the user's input and send it to the UserInputValidator to be cleaned
  • modified the display results table for three different cases:
    • when a search is invalid
    • when a quote is not found
    • when quotes are found
      • if quotes are found: these are displayed as a tkinter 'Treeview' with scrollbars

Screenshot of a result for searching by quote with 'love'

Corresponding ticket: #19 (closed)