Switch to Linux kernel coding style

Use the Lindent script from the Linux kernel tree to reformat our
sources, without wrapping long lines. We need to refactor code and
reduce the number of nested blocks before line wrapping can be done
properly. Note that the Linux kernel coding style is very close to what
is used in libpurple (https://developer.pidgin.im/wiki/CodingStandards
for details).

Signed-off-by: Lukas Fleischer <info@cryptocrack.de>