Fix regression in rendering the Window-Motion-Outline

Commit 79fe2fca1de5140f538e68f6981b27cf7f917e7a checks for pending
motion events and drops out of the FluxboxWindow::motionNotifyEvent() function
early if so. When the user does not use the opaque window movement method an
outline will be drawn to the screen. That outline was not cleaned correctly
with commit 79..
fix head detection for adjacent heads of too different sizes and window placement based on apps file

* if you have e.g a 1920x1200 monitor and a small 800x600 monitor to the
  right of the bigger one and a small window at the right side of the
  big monitor (but still the whole window area at the big monitor) then
  the original head detection would claim the window is on the small
  monitor because (800/2+windowWidth/2 < 1920/2+windowWidth/2) is true
  for small windows; but that is obviously wrong, the window is entirely
  on the big monitor
* these incorrect head detections did lead to incorrect window
  placements as they were required in the apps file
fix initial window placement to allow proper head detection and window placement based on apps file

* a reasonable initial placement is important for later movements to
  different heads and correct head detection (required by apps file)
* it did not work well in case when (0,0) was not near any head
minor
Use shared code, minor code simplification
more compact code
Removing a blank line in nls/it_IT/Translation.m that breaks the -help output.
build-sys: use automake subdir-object
build-sys: remove unnecessary files
docs: update Doxyfile

Just a simple 'doxygen -u' version update.
build-sys: include config.h to all files using automake

Do not try to be too smart which compilations need config.h, as most of
them will simply because of the config.h has information about system
capabilities.
build-sys: use AC_USE_SYSTEM_EXTENSIONS

The earlier _GNU_SOURCE definitions possibly did not take effect
everywhere where it was intended.
build-sys: move autotools files to subdirectories
build-sys: use pkg-config to locate dependencies

This commit alters XRANDR (X Resize And Rotate) extension dependency,
which is expected to have at least version 1.4.  Earlier old versions of
xrandr were supported, at least to some extent.
build-sys: add test programs to .gitinore file
build-sys: unify configure.ac syntax
build-sys: use iconv library detections from gettext

This patch took copy of config.rpath from gettext 0.18.2 to build-aux/
directory.  Software projects usually does not need to do that, because
the file is copied by gettext autopoint in autogen.sh or bootstrap.

In Fluxbox case calling autopoint seems wrong, as it would generate po/
directory with necessary make automation, adn 'msgid' & 'msgstr' files,
but that is not how the translations are done in this project.
build-sys: move to non-recursive build

This rather large change will attempts to make 'make' to work better.
See excellent paper 'Recursive Make Considered Harmful' by Peter Miller
for further explanation why several make files is worse than one for
whole project.

Note.  The tests are build with 'make check' rather than defining TEST.

Reference: http://miller.emu.id.au/pmiller/books/rmch/
Reference: http://karelzak.blogspot.co.uk/2013/02/non-recursive-automake.html
build-sys: use compiler header search path

Instead of having reletive includes such as

make the compiler to find the includes for a programmer.  This way the
internal libFbTk will behave more like a normal library.