Set version number to "1.3 (dev)"
Restructured Sound page

* Since the mixer modules don't line up with the oscillator, graphically
  it's hard for the eye to connect the oscillators with the mixer sections.
  Therefore, remove the mixer boxes, and put the mixer controls for the
  oscs in the respective osc boxes, and have separate boxes for the
  noise and ring mod modules.
* Augmented ring mod and noise boxes to be more informative.
* Haven't fixed the key mappings, get key mapping errors during
  midiedit startup.
Fixed key mappings for new Sound page layout

* X key still goes to Osc 1 level, from there 1, 2, 3 go to Osc 1, 2, 3
  level, respectively.
* If Osc 1 balance is in focus, then 1, 2, 3 go to the respective
  balance parameters.
Use one single table for Sound page

* ... rather than a combination of vboxes and hboxes. This makes it
  easier to line up the filter and osc boxes, which did not quite line
  up before for whatever reason.
Swap noise and ring mod

* This way, the noise mix settings are directly under the oscillators,
  and the ring mod section to the right of the osc common frame.
Fixed a couple of excess-space-before-parenthesis
Fixed some comments
Fixed getting patch dump after selecting buffer no with keys

* Selecting the buffer number using up and down keys followed by
  enter now requests the buffer, just as clicking it does.
* Note that just moving the focus with the arrow keys does not do it,
  it is necessary to press enter when the desired buffer number has
  been reached.
Underline 'x' in Osc 1 'mix' label to show hot key used
Set version number to 1.3 for release
Merge branch 'dev'
Added release notes for 1.3
Merge branch 'master' into release