VERSION 1.1.8: minor Linux bug fix, controller fixes, controller doc …

…improvements

1.1.8 is a very minor update. It contains a small fix to IP address management
on Linux but other than that there are no changes to the regular ZeroTier One
code.

The 1.1.8 controller contains several fixes and improvements:

 * Network authorizedMemberCount works again
 * Managed IP addresses are pushed as long as they fall within a LAN-local managed
   route. The v4AssignMode and v6AssignMode settings only control automatic IP
   assignment from pools. In previous versions v4AssignMode had to be on for IPs
   to be pushed at all, making it impossible to just manually assign IPs.
 * IPv6 now has an auto-assign mode ('zt' to match V4) that can work alongside the
   special RFC4193 and 6PLANE modes (though it is not NDP emulated). If this is
   enabled IPv6 addresses will be auto-assigned from IPv6 ranges in the assignment
   pool list.
 * Controller documentation is MUCH better! See controller/README.md for actual
   useful information!

Finally 1.1.8 has several improvements to linux-build-farm including Debian wheezy
support.