Test code which wants to customize config.h can do so without
touching config.h itself by wrapping config.h in a macro variable
which is passed in to the compiler. It defaults to "config.h" if
no override is provided.
This change would break makefile dependency checking since the selection
of a different header file on the command line is not noticed by make
as a build-trigger. To solve this, we add a layer to the BUILDDIR path
so build products are now specific to the USER_CONFIG choice if it is
not "config.h".
##############################################################################
# #
# Teacup - lean and efficient firmware for RepRap printers #
# #
# by Triffid Hunter, Traumflug, jakepoz, Markus Hitter, many others #
# #
##############################################################################
For installation instructions, see
http://reprap.org/wiki/Teacup_Firmware#Simple_Installation and/or
http://reprap.org/wiki/Teacup_Firmware#Developer_Installation
For documentation, see
http://reprap.org/wiki/Teacup_Firmware
##############################################################################
# #
# This firmware is Copyright (c) ... #
# 2009 - 2010 Michael Moon aka Triffid_Hunter #
# 2010 - 2013 Markus "Traumflug" Hitter <mah@jump-ing.de> #
# #
# This program is free software; you can redistribute it and/or modify #
# it under the terms of the GNU General Public License as published by #
# the Free Software Foundation; either version 2 of the License, or #
# (at your option) any later version. #
# #
# This program is distributed in the hope that it will be useful, #
# but WITHOUT ANY WARRANTY; without even the implied warranty of #
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the #
# GNU General Public License for more details. #
# #
# You should have received a copy of the GNU General Public License #
# along with this program; if not, write to the Free Software #
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA #
# #
##############################################################################