Added get_ncomp and get_rms meta data functions and associated read elements.
Added paper cataog and a few changes to img.py from way back.
Added paper catalog. 5Jy peeling exclusion on but none found.
Merge git://github.com/AaronParsons/aipy into catalogs
Merge commit 'HEAD'; branch 'stokes' into catalogs
Folded in standardized fits header mod.
Made sure new paper catalog is importable.
Added some source introspection to phs and amp.  Try printing a source made from a RadioFixedBody class in either of these.
Merge git://github.com/AaronParsons/aipy into stokes
Adding the pol.py module from from previous work.  Unstable!
Added support in the --ant input arg for ant-pol notation. eg 5x_2y for pol xy on bl 5_2.
Mixed notation allowed. eg 5_6y to get 5x_6y and 5y_6y.
"Improved" polarization handling in antenna option.
Corrected small errors in paper catalog.  Added scripting.get_null_aa() for when an antenna array
with no specific parameters is needed to run update on a source.
Merge branch 'master' of git://github.com/AaronParsons/aipy
Added history option to fits writing in img.
Added propigation of uv history to img history in mk_img.py.
Merge branch 'master' into stokes
Fits history tested.
Added a function to create a new fits based on an existing file.
Fixed up some header bugs in img.from_fits_to_fits.
Fixed a typo in from_fits_to_fits