undo nested clip bug, wheel zoom redraw fix, uninited vars, shortcuts doc
update shortcuts doc, period/comma alt shortcuts, popup deactivate fix, click2play enable
merged hv7 mod
picon dirs, new cinfinity picons, plugin info, rework text drawing, show msg, compressor fix
assetedit/resize track fixes, dangling popup threads
titler fixes, auto paste bug, resize popup hang, focus policy fix, chk lang
add browse bg btn in titler, prevent a few badwin signals, titler text popup upgrades
VBR for ffmpeg mpegts, user mount for udf images, widget fixes
popup menu mods/pref, pactl fix
improve resize flash operation, fixup xv grab/ungrab, fixup label updates
change popupmenu behaviour, few minor fixups
rework keyframe hide popup, keyframe auto render, textbox set_selection wide text
merge: mask fixes/upgrades, overlay plugin rework, popup menu tweak
Merge CV, ver=5.1; ops/methods from HV, and interface from CV where possible