This is a set of kludgy fixes for MathML attribute and entities support.
It is intended that a full HTML5 entity table be added at some time, but
at present ALL entities are accepted as written when within the math
element.
Likewise all attributes are accepted on MathML elements without any check
of their name or value, even if they match attributes outside MathML.
And in the pprinter such entities are written as is from the lexer, using
a new PPrintMathML service added, using the new mode OtherNameSpace.
It is hoped all these fixes will NOT effect tidy outside the math element.
ALL fixes in the set a clearly marked '#130 - MathML attr and entity fix!'
for easy searching, and improving if possible.
An immense thanks to Ger Hobbelt who had already done this
in his github.com/GerHobbelt/htmltidy fork.
The two sources have diverges so was not a simple cut
an paste. But again thanks Ger for this.