editor: do not autoscroll with zero-width trackview

This fixes a glitch where the edit-track is invisible when loading
documents from the command line.
player: do not emulate inline as static

All our inline functions are already declared as static inline,
and multiple static declarations gives compiler errors. So let's
just define inline empty.
player: build non-client variant from makefile
editor: do not paint interpolation-mode into the previous row
editor: pimp the statusbar

Use OS-default layout, by adding permanent widgets and setting the
message separately. Also go for the OS-default look, by not styling
the panels.
Merge remote-tracking branch 'origin/master' into editor-structs

Conflicts:
	editor/mainwindow.cpp
	editor/mainwindow.h
	editor/trackarea.cpp