separate portal from main panel
set sandbox as the composition button text
make portal a toolbar widget
add separators to toolbar
move play button to portal
fix layout and spacing
add visible frame to typewriter
set composition view minimum height
adjust sizing and stretch
remove obsolete custom separator
Merge pull request #190 from cyberixae/fix_portal_buttons

Fix portal buttons
always show composition view
reorganize layout
Merge pull request #194 from cyberixae/remove_splitter

Remove splitter