Implementation namedtuple for Python2.4

From http://code.activestate.com/recipes/500261-named-tuples/
NOTE we need this here because we don't have namedtuple in Python 2.4, the
version of Python used by Squish
New utilities of finding and getting text of SWT Tree Items

adapted from http://kb.froglogic.com/display/KB/Example+-+Getting+TreeItem+of+SWT+Tree+via+path+(Java)
Starting point for suite_tools1d_functionfitting

New testsuite for function fitting tests in squish.
Includes generic routines for manipulating and verifying function
fitting.
DAWNSCI-5676: Add regression test for fixed function fitting bug

This is the test for the fix in dawn-ui.git:c7277e9
Merge branch 'DAWNSCI-5676-function-fitting'