Added accesslvl & fixed the log system.

Accesslvl is split in to two options during the registration of a new
admin, 'full' and 'semi'. Full has access to every feature on the
control panel, whilst 'semi' has access to everything apart from new
admin registration and the ability to view the map over vehicles,
players or tents. While still being able to view grid-refs since they
are not entirely accurate.