Obtaining systemtap version information from stap

[William Cohen]

Going through and writing the tests one of the things that did come in 
handy for the OProfile tests was being able to query the executable for 
the version. Some of the oprofile testing framework makes use of that 
information to determine which tests should be run or which commands 
could should be used. As oprofile evolved some of the commands changed 
and some of the output changed. Being able to get the version 
information made it possible for the tests to determine the correct 
input and output to use.  It would be good if there was some way to 
query "stap" for the version being used.

-Will