Toolbox Colors sections: Use consistent terminology and sync strings
- Do not waste translators' time by unneededly describing the same stuff with different words.
- These areas are not "icons" but areas.
- Do not use both "Tools Indicator Area" and "Brush/Pattern/Gradient" to describe the same thing.
- Do not use both "Color Area" and "Foreground/Background colors" to describe the same thing.
- Do not use "FG/BG" abbreviation without explaination.
- Cover on both pages that two of the three areas are not even visible by default.
- Correct link to Toolbox preferences page.
- Link to docs for mentioned "Images dialog".