babeld: migrate from openwrt/packages

- Update maintainer email address
- Wait for babel to die in init script (avoid race-condition on restart)

Signed-off-by: Gabriel Kerneis <gabriel@kerneis.info>
babeld: new upstream release 1.5.0

22 May 2014: babeld-1.5.0

  * Added support for an RTT-based metric -- see the description of
    "enable-timestamps" in the manual page.  This work was done by
    Baptiste Jonglez with help from Matthieu Boutier.