Add 'install-python26' Makefile target
Add 'install-python26' Makefile target

The install-python26 target installs into the Python 2.6 site-packages
dir and uses '/usr/bin/python26' as the #! line for Python scripts. It
required splitting out an 'install-common' target from 'install'.

/usr/bin/python26 comes from the python26 package from EPEL5 and will
allow using newer versions of osg-build on EL5 once I drop Python 2.4
compatibility.

git-svn-id: d4dac5d1b57f4ff5e3fed9c080589c4820ad2c03@22520 4e558342-562e-0410-864c-e07659590f8c

opensciencegrid/osg-build,opensciencegrid/osg-build,matyasselmeci/osg-build,matyasselmeci/osg-build