configure options

[Boyana Norris]

This is a suggestion for a trivial addition to what goes in configure.log 
(that is, if it's not already available elsewhere). One feature that I've 
found very handy in the otherwise unpleasant use of gnu configure is the 
ability to cut and paste the options given to configure from the config.log 
(or .status) file, in the case when building multiple versions or slightly 
differently configured builds. This doesn't seem to be available with 
PETSc's configure, or at least not obviously so. If I take the array of 
options from configure.log, I can't just paste it on the configure command 
line.

Boyana