Alternative CHM presentation

[Dainius 'GreatEmerald' Masiliūnas]

The CHM (Microsoft Compiled HTML Help) file format used for displaying help files is overall very unfriendly. It is an old format, barely supported even on current Windows. Wine implementation of it is also fairly lacking (it depends on emulated Internet Explorer, and overall it is of low importance to Wine). Plus the file format is proprietary, so it cannot be changed easily, and we want to do that to have localisation and updates. Even right now the help file is full of Windows-specific terminology.

It could be extracted into an ordinary HTML file, with the "help" button opening the default web browser. That's pretty much how help works in Pidgin, for instance. That would also allow git to easily track changes to the help file.