The Mage talent Arcane Concentration, in the Arcane tree, provides a Clearcasting buff.

It is unclear whether tracking this buff is really useful or not:

• in many cases, this buff doesn't change the mage's dps cycle at all, it can be seen as a passive mana regen
• in some cases, mages will spam spells which cost very little mana to look for a Clearcasting proc, and then cast a big spell

If tracking Clearcasting is considered useful, a texture must be chosen, along with a place to put it (left/right/top/elsewhere).

Implemented in #99.

The chosen location is Left/Right, but with bigger size than usual to minimize overlapping.

See PR description for more information.