Changed the minimum font size for percentage size text from 10 pixels height...

Changed the minimum font size for percentage size text from 10 pixels height to 1 pixel height.   When the font height in pixels gets too small, an OpenGL warning is logged at the 'warning' level.  It appears that the OpenGL errors may be caused by specific characters within a font and not necessarily the height of the font.  In addition, the font errors were also found to be different on Mac and Linux.