[Buildroot] [PATCH 0 of 4 v2 for-2014.05] website: some limited updates

[Thomas De Schampheleire]

These patches make a few updates to the buildroot website:
- update contribute and support page
- remove references to uclibc.org
- add alt property to img tags (correct html)

Signed-off-by: Thomas De Schampheleire <thomas.de.schampheleire at gmail.com>

---
 docs/contribute.html |  53 ++++++++++++++++++++--------------------------
 docs/docs.html       |   2 +-
 docs/header.html     |   3 ++-
 docs/index.html      |   3 ++-
 docs/js/buildroot.js |   2 +-
 docs/support.html    |  32 ++++++++++++++++----------------

Note: it seems that lists.buildroot.org forwards to bugs.busybox.net instead
of staying at lists, which makes the list URL unchangeable, currently.