0.3

CHANGES:

Breaking changes:

• Don't allocate a fixed buffer by default (@talex5 #53).
  If you want a fixed buffer, you now need to call set_fixed_buffer.

New features:

• Add sendmsg and recvmsg (@patricoferris #49).

• Allow sending and receiving FDs using SCM_RIGHTS (@talex5 #52).

Other changes:

• Update tests to cmdliner 1.1.0 (@patricoferris #50).