Anchored Brushes: Options to Flip X / Y

Situation: Currently to flip an anchored brush, the only way to do so is to go to the texture and flip the texture. This adds additional clicks and might also affect other assets in case the texture is used for something else.

Improvement Idea:

• Add two options to the Brush Settings: Flip X and FlipY (Z is already covered by the option "Direction" for Z Brushes)

Benefits:

• Enables a very fast switch of the orientation of a brush.
• Does only affect the brush, not the texture.
• Allows users to change the orientation of a brush to fit the way they prefer to stroke with anchored brushes (up, down, left etc...)