Fixed active task and task creation bugs:

. Adding a task now calls getTasksByTag to avoid loading all tasks
. Active tasks are now checked for in getTasksByTag to ensure active task isn't listed in task list
. TaskList is reloaded and active task refetched when task is made active
.. Keeps consistent-ish styling of active tasks
.. Active tasks still need edit and delete buttons, as well as a way to unload them

. Delete 'button' now has an id to differentiate it from the li to stop delete from changing the style of the entire list. This was a bug introduced in the last commit.