No version defines in libcli.h

[amishHammer]

Hi,

There are no version number defines in libcli.h

This makes it hard for consumers to work out what version of the command callback prototype to use.

The change between 0.9.5 and 0.9.6 for example broke the razorback builds.

For this release I guess I will have to implement version checks with compile tests in autoconf.