Added a "lag" command.

Added a "lag" command to allow users to quantify their lag. It simply sends a /CTCP PING to the user and processes the reply. Changed processPrivateCommand() to processPrivateMsg(). Fixed indentation by replacing tabs with spaces.
Added "admin"/"deadmin" commands. Small fixes.

Added the ability to add and remove users from the admin.txt list through the bot. Fixed typo. Added a list of admin commands when an admin uses the "commands" command.