gui: GUI definition update
gui: Added extra info about NumberSlider change
gui canvas: mpp correction in fit content to view
gui: GUI layout fix
gui test: Overlay fix
gui miccanvas: remove fps_overlay from overlays when it must be hidden

use the new style of handling overlays: just update the list of overlays according to what must be drawn
Merge branch 'master' of vpn.delmic.com:odemis
gui: no need to refresh canvas on hide_pause anymore

it's done automatically
gui: some clean up in overlays

should not change behaviour
gui overlay: small improvements to dicho overlay

never allow to show more than max_len
increase max_len by 1 for more precision
set line width to 2, to make it shaper