xspec patches from April

A few problems in 12.6 have been identified and patched. Information and patches are available on the xspec bugs page.

12.6.0c	The setplot rebin option does not work properly when used in energy/wavelength mode AND channel energies are listed in descending order in the response EBOUNDS extension. Our thanks to Roderick Johnstone for pointing this out. Report added on Apr 01, 2010.
12.6.0d	The chi-square does not change when running steppar on the redshift z parameter of a table model. Our thanks to Jeremy Sanders for pointing this out. Report added on Apr 08, 2010.
12.6.0e	This improves the initpackage local models tool so that it now recognizes *.f03 file extensions for Fortran 2003 code, and it also now allows *.f90 extensions. Our thanks to Pablo Cassatella for bringing this issue to our attention. Report added on Apr 15, 2010.
12.6.0f	For better compatibility with previous XSPEC releases, when multi-panel plots are performed interactively with iplot, the first panel should be designated PLT's currently active window rather than the last panel. Our thanks to Maria Caballero-Garcia for pointing this out. Report added on Apr 21, 2010.
12.6.0g	This increases an internal buffer for handling PLT command strings. A larger size is now necessary when producing multi-panel plots which happen to contain a large number of plot vectors. Our thanks to Lijun Gou for pointing this out. Report added on Apr 30, 2010.
12.6.0h	A couple of modifications to the behavior of steppar when not starting from a best fit: The delta fit statistic column will now show values relative to the original fit statistic, not the value it has after steppar performs an initial renormalization. Also when steppar detects a new best fit, it will now prompt the user only when the improvement exceeds the current setting of the fit's critical delta parameter. Our thanks to Jeremy Sanders for this suggestion. Report added on Apr 30, 2010.