Adds renameId functionality

Commit adds the ability to rename an existing ID

Also a small bug fix to the add new ID in which if an error occurred,
the flag wasn't reset and was stuck in an infinite loop.
Severe Bug Fix and Refactor

Finally pinned the elusive bug that was preventing proper removal of
existing IDs that also affected ID renaming.

Also refactored the saveToKeyFile and removeId functions to use a
QVector instead of just a QString.
Fixes Header Labels
Fixes error message boxes

There was an issue with the formatting on the error boxes