configure.ac: change the version string so it does not contain parens   (`make dist` doesn't like them).
configure.ac: change the version string so it does not contain parens
  (`make dist` doesn't like them).

google/crush-tools,google/crush-tools,google/crush-tools,google/crush-tools,lexsf/crush-tools,google/crush-tools,lexsf/crush-tools,lexsf/crush-tools,lexsf/crush-tools,lexsf/crush-tools,lexsf/crush-tools,lexsf/crush-tools,google/crush-tools,google/crush-tools