Fixes for api changes.
Max value of scroll isn't updated anymore, needs property callbacks to make it work again.

- added next/previous buttons so you can skip demos.

* Moved property definitions to registration function.
* Changed automatic callback adding to manual, the current API doesn't seem to allow this top be automatically yet.

work in progress addon: demo mode, use for easy setup for looping over blend files, rendering, playing, switching screens.

removed warning, api r35853
quick fix for error.
line 519 commented out > # bpy.ops.object.location_apply()

added "warning": "Script returns errors"
api r35853

"warning": "Script returns errors"

Modified the wiki_url link to point to the MH site. To link to external sites may be frowned upon, but I don't want to maintain duplicate copies of the documentation. This is at any rate better than before, when the the link pointed to outdated info.

from perfection cat (sindra1961) 

Matrix().Scale --> Matrix.Scale

eg: XFCE file - /usr/share/xfce4/xkb/flags/tr.svg

Transformation for non-container objects was applied twice when they were USEd.
Get rid of confusing checks for special cases in USE.createGeom and use special
flag (instancing) which tells geometry is it "normal" geometry creation or
geometry creation initiated by USE node (SYMBOL would be handled differently
int this two cases)

Quick tests showed none regressions.

Suppose zero frictional part for case there's space or comma after
dot in float value. Inkscape sometimes uses such weird format.

- transform() only requires a single argument.
- support 'INVALID' as a unit suffix is present in some files created by docbook.

file from report [#26555] was raising an error becaues of this.
us.svg line 23
  <use xlink:href="#star" x=" 0.126"/>

Enable raytracing on OBJ materials always, not conforming to OBJ spec but this is annoying for newer software where raytracing is default.