Changed color palette to display colors in a variable number of columns
depending on the width of the palette.
Implemented a new wrapping layout container for the tool palette.
Modified the Color Palette Widget to so that it will arrange
itself horizontally if it is wider than it is high.
Introduced a change from the MonoDevelop Docking library which stops
docked palettes resizing when the window is resized.
Changes for horizontal and compressed color palette layout
Merge pull request #71 from don-mccomb/bug581108

Fix #581108 - Palette and toolbox should be flexible and take up available horizontal spac