sbank_plot_sim: generalize applicability of spin effeciency plots
Implement PhenomP for banksim
Remove LAL_ prefix from all lal constants
ligolw_print, ligolw_cut:  small clean-up

use super() to chain to parent class in custom content handler
ligolw.py:  derive all content handlers from LIGOLWContentHandler

affects PartialLIGOLWContentHandler, FilteringLIGOLWContentHandler
ligolw.py:  compare pcdata to None instead of casting to bool

small performance improvement in some conditionals
ligolw.py:  clean up Comment and Param .write() methods
array.py:  simplify Array.get_shape()
ligolw.py:  fix regression in PartialLIGOLWContentHandler

regression was introduced in 679b9592893904f182c5b67504533ba2fd4161b1.
causes document loading to take *forever* and use lots of memory
ligolw.py:  partial and filtering content handlers must strip text

this prevents character data from elements that have been removed from the stream from being appended to other elements
ligolw.py:  disallow .appendData() for elements that don't allow text

methods now raise TypeError if non-whitespace text is appended to elements with no text content
ligolw.py:  report line numbers in content hnalder failures