Have been around since 2.6 but undocumented, add it since it is
useful in multi-display setup.

wx did not build with wxWidgets-3.1.1 since they have removed
wxGraphicsRenderer:CreatePen(wxPen).

Get the pen info and create the pen from that in 3.1.1 as
is done for wxGrahicsContext:CreatePen(wxPen).

Some taylormade functions still used edoc spec's, and some
where wrong which caused broken links.
Change them to be real spec's and correct the types.

Follow the convention and make atom more visibile in types and specs

Commands could be executed twice, if the command was dispatched
from a callback and caused a recursive invocation of command loop.
Solution is to mark op as -1 before calling wxWidgets.

Also commands could be missed when idle processing was done inside
while executing a recursive callback, solved be always resetting peak
index after idle processing is done.

This is really needed on windows to get rid of flickering when updating
some widgets. These functions are only available if 3.0 and not on mac
where everything is double buffered already.

Available since 3.0

Some events are callbacks inside wxWidgets so idle processing doesn't
take place until operation is completed, for instance move/resize window
on Windows. This way we get some response while mouse button is pressed.