Add some path searching for the ap{r,u}-config files. Also, pick up the correct version (e.g. apr-1-config).
Add some path searching for the ap{r,u}-config files. Also, pick up the
correct version (e.g. apr-1-config).

* serfmake:
  (class ConfigScript): new base class for -config scripts
  (class APRConfig, class APUCONFIG): set the class constant for the right
    script name.
  (class ConfigScriptNotFound): new exception when a -config cannot be
    found on the path.


git-svn-id: 683495cb1553624b05a54e2ba9533425f69cf277@905 61a7d7f5-40b7-0310-9c16-bb0ea8cb1845

coapp-packages/serf,coapp-packages/serf,coapp-packages/serf