devel/edelib: Add version 2.1

Small and portable C++ library for EDE (Equinox Desktop Environment).

Aims are to provide enough background for easier EDE components construction
and development.

Upstream changelog for version 2.1
----------------------------------
- Added tooltip support for menu items.
- edelib can be compiled without DBus binding. EDELIB_HAVE_DBUS #ifdef can be
  used to check if edelib has DBus support.
- Added edelib-dbus-explorer, a dynamic UI tool for exploring and communicating
  with DBus services via a builtin Scheme interpreter.
- Fixed various bugs in bundled Scheme interpreter, detected after TinyCLOS
  tests.
- Faster (append) and fixed (gcd) and (lcm) in Scheme interpreter.
- Added JSON module for Scheme interpreter.
- Added workaround for missing _SC_GETPW_R_SIZE_MAX on Minix.
- Added str_hash() function for simple hash computing from string, which
  unified hashing code through edelib.
- edelib now ships its own rgb.txt as the Minix X11 distribution keeps it in
  uncommon places.
- Theme engine is using C++ RTTI (optional feature) to figure out how to update
  widget fonts.
- Fixed a couple of warnings produced by clang.
- Font cache engine will prevent registering fonts if already registered.
- FontChooser is now using font cache for querying fonts.
- edelib-convert-icontheme can use rsvg-convert now.
- Redesigned icon chooser dialog: now the user can also choose icons not found
  in the icon theme.
- Small dir_list() optimization.
- Fixed core dumping for bundled Jam on Minix.
- Added support for querying NETWM window states.
- Expandable group can now read global scrollbar size.
- Icon theme engine now supports searching for icons when exact icon size wasn't
  found; this completes full support for fd.o icon theme specification.
