options:
(a) enable Markdown support,
(b) add a Mainpage,
(c) do not strip comments from code,
(d) use Doxygen's default header and footer without timestamp,
(e) enable the search box.
1. Use <stdbool.h> if it is available but keep a compatibility shim in
shared/defines.h in case it is not.
2. Unbreak the circular header dependencies (mostly):
2a. client.c and client.h may NOT depend on 'struct Menu'. Use a void pointer
and casts instead.
2b. Separate the data type definitions in client.h and screen.h from
function prototypes which may require other data structures. This makes
header dependencies much more easy to maintain. Usually the data types
should have been moved to their own files but I (mmdolze) chose to
separate them using different header guards.
2c. Remove many now unused header includes.
Apply (old BSD-) style on menuscreens.c.
1. Remove connection type header files and put prototypes locally and in
glcd-drivers.h. Don't fall into the pitfall of too many header files again.
2. Create a separate frame buffer structure (this allows easier re-use of
the frame buffer functions).
3. Add a function to retrieve pixel values from framebuffer.
4. Add the 'serdisplib' connection type.
5. Support display width that are not a multiple of 8 (e.g. 122x32).
* The full block icon now has index 0 and the heart has index 7. This makes
the full block work if vBar custom chars are loaded (which use index 1-7).
* Prevent (hbar, vbar, bignum) modes from overwriting custom chars (except
full block).
* Prevent the heartbeat from overwriting custom chars in vbar and bignum mode.
* Make the driver point to 0x1A and 0x1B characters for right/left arrow
characters (those are the codes from HD44780 A02) and make all charmaps
pointing to the correct characters.
* It is now possible to map the tilde character.
* Update other drivers that use hd44780-charmap.h (IOWarrior and ula200).
* Replace characters using charmaps on input instead of output!
* Remove some unnecessary comments.
mmdolze