Fix alignment of unstyled text.

Separate out the offset from the text alignment, and use the
text alignment to set the bounding box.
Fix shape and initial position.
Merge pull request #312 from softins/unstyled-text

Fix alignment of unstyled text.
minor/typo fixes
update MusicXML website in about box
fix #20997 fix #19149
fix #15943: Tuplet creation from empty measures (whole rests)
change text in staff properties dialog
fix regression: position of instrument names
experiment new color and thickness for breaks and spacer to make them more discrete
rename icons according to FreeDesktop Icon Naming Specification
change icon set
add align-vertical-baseline icon, fix alignment icons in Style->Text
fix resource file for Mac OSX
replace more icons
replace more icons, take 2
fix #11684: replace 'Display' by 'View' in the main menu
fix annoying bad french translation, impossible to export PDF
no icons in menus, even on Windows
add missing format-indent-more icon