apache: bump to 2.4.41 & sync with master

This is a squash of the following cherry-picked commits:

14f4f0be
4e6bdd8a
c8aba511
2d188fd3
31e0d618
39e68309
a1472254
d6476f30
258967b0
e94a0829
6bd63d24
66bb68a7
d44ad09f

Short summary:

- version is bumped to 2.4.41
- httpd is renamed to apache2 to avoid overwriting of other servers (for
  instance busybox's httpd)
- the name apache2 is now also used for directories, for instance
  /etc/apache2 instead of /etc/apache
- a simple init script it added (/etc/init.d/apache2)
- a user "apache" is added upon package installation and used by default
- adds the Apache modules (in the main package as well as in additional
  packages)
- Makefile and patches are updated and cleaned
- adds myself as maintainer
- improves the cross-compile setup (via configure variables, patches &
  sed scripts)
- apxs is fixed up so that external modules can be added easily

For more details please check the individual commits provided above.

Signed-off-by: Sebastian Kemper <sebastian_ml@gmx.net>