tags: Support battle pets' level

Fixes #172
Merge pull request #173 from p3lim/level

tags: Support battle pets' level
totem: Destroy the OnClick handler.

DestroyTotem() is currently protected and there's no easy way to handle
this.

Fixes #168.
TOC: Bump interface version to 50200 (5.2).
TOC: Bump version to 1.6.2.
units: Don't poll on boss unitids.

They are proper units now. Yay!
tags: LIGHT_FORCE was renamed CHI.
core: Ues the 5.2 secure unit dropdown.
TOC: Bump version to 1.6.3.
core: Adding togglemenu to header units
Bump TOC version to 1.6.4.