Implemented percentage outline width for text rendering. For previously...

Implemented percentage outline width for text rendering.  For previously created text annotations, the percentage line width is invalid.  When an older text annotation with an invalid percentage width is drawn for the first time, the obsolete pixel line width is converted to a percentage line width using the height of the viewport in which the text annotation is drawn.  This new percentage line width is then updated in the text annotation which can have its file saved or scene saved (scene annotations).