Re-wrote 'sifting.py' to be slightly more modular.

Also, added summary plots.
Merge branch 'master' of git://github.com/scottransom/presto into sifting
Add support for old sifting API.

Update plots. Add possibility to write out report of why bad cands where removed.
Reset global variable to original value.

Other minor changes. Add todo in sifting function. Change notes for long/short period rejections to include units (now ms instead of s).
Fix how sifting globals are retrieved.

Old method for getting globals did not return the correct value if they were updated. The current method is ugly, but works by grabbing the values from the global symbol table.
Added function to create polycos from parfile.

Also, added some functions to get rotations, frequency, phase at given MJD.
Merge branch 'polycos' into inject
Merge branch 'inject' of github.com:plazar/presto into inject
Re-factor how 'injectpsr.py' deals with pulse profiles.
Move 'injectpsr.py' to bin dir and add execute permissions.
Add missing '!' in hash-bang (#!) in 'injectpsr.py'
Re-factor 'injectpsr.py' to make it easier to run the profiler.

The code is slow.
Major changes to 'injectpsr.py' to get it working.

Still needs more testing.
Add soft link to 'injectpsr.py' in lib/python dir so it can be imported more easily.
Fixed -00 deg DEC bug noticed and patched by Ben Knispel.  Thanks, Ben!
Two patches from Anne Archibald:  warn about non-pow-of-2 prof/template lengths and default to same # TOAs as # parts in time
Add pointer to 'bin/injectpsr.py' into 'lib/python' so it can be imported if necessary.
Add ability to append spectra to filterbank format files via python FilterbankFile objects.
Check if FilterbankFile is writable.
When injecting append spectra to empty filterbank file instead of copying and modifying.