Update UG webpage

Add FindCommand and modify TaskList.findTasks() method

Add Time class for date and time parsing and formatting

Refactor: Extract Ui, Storage, Parser, and TaskList classes for better

modularity and clarity.

Add javadoc comments for classes and methods

Merge remote-tracking branch 'origin/master'

Merge branch 'branch-Level-7'

Merge remote-tracking branch 'origin/branch-Level-6'

Merge remote-tracking branch 'origin/branch-Level-6'

Improve UX

Allow more flexibility in commands format, the user can add any number
of white spaces between the task the time