Warn if multiple .ahk files exist in startup folders

[rikedyp]

If the user chooses to launch at startup, check if there are already .ahk files in the startup directory and warn the user (possibly offer to delete those or open the folder in Explorer).

Further, the save-to folder should be blank by default, and a blank value means not to save the script.

[rikedyp]

Going to remove startup stuff and simply document how to do this for users

[rikedyp]

removed save to startup folder in APLAutoHotKey and documented where to find startup folders instead