Merge pull request #204 from pmienk/master

Isolates auxiliary files generated via autogen.sh/autoreconf.
Check that -D_FORTIFY_SOURCE=2 doesn't trigger a compiler bug
Merge branch 'master' of github.com:jedisct1/libsodium

* 'master' of github.com:jedisct1/libsodium:
  Prevent first-run ./autogen.sh error due to ltmain.sh absence.