Revision 44123

Some improvements to german d-i manual:
M    de/preface.xml
M    de/partitioning/partition/x86.xml
M    de/appendix/files.xml
M    de/appendix/graphical.xml
M    de/welcome/what-is-debian-linux.xml
M    de/welcome/what-is-debian.xml
M    de/hardware/hardware-supported.xml
M    de/hardware/supported/alpha.xml
M    de/hardware/supported/sparc.xml
M    de/hardware/supported/mipsel.xml
M    de/boot-installer/alpha.xml