* Update Travis
* Drop Older PHP Versions
Drops PHP 7.1 and 7.3 from tests. Also updates Translations to use PHP 7.4 instead of 7.3
* Update Test Class Names to Fix Warnings
This updates the Class name for 'CategoryTest', `passwordUtilTest.php`, and `MigratorTest.php`
* Keep the user on login page on failure
* Show an error if username already exists
* Check the password format in the backend
* Return a better message if username is invalid
* Add a title to the login page
* wip: Improve look of login and register pages
* Set a capital M in username help message
On the registration page, username tip started with a minuscule, while
the password tip started with a capital.
* Change message if username is taken
