[krbdev.mit.edu #6311] kadmin utilites could support better command line editing

[Mark.Phalan@Sun.Com via RT]

libtecla provides a enhanced command history and editing function for
use by applications.  This would be useful for kadmin since it has a
interactive mode through which users provide commands to kadmin.
libtecla would provide command tab-completion, line editing etc.

Attached is a patch which adds libtecla support to libss (used by
ktutil,kadmin/kadmin.local).

The patch currently doesn't change the build system. The code here is a
direct port from OpenSolaris where we use a static build system. My
auto* foo is weak...

Included in the patch is an update the the license the contributed code
is under.