Boostbook: Fix for libxslt 1.27.0.

libxslt now seems to think that $uppercase-letters and $lowercase-letters are
undefined at this point. I'm not sure if it's right, or if this is a regression
in libxslt, but it's easy enough to get working, and while it isn't ideal, it
isn't too problematic.
Boostbook: Simpler method for copying chapter attributes. Refs #7899.

I'm not sure if this will fix the issue, but it's worth a try.
Boostbook: Fix `run-tests.py` for new `generate-id`.

The form of the generated ids has changed due to a security issue.
Boostbook: Regenerate the "gold" test docs.

The ids are now a little more truncated than they used to be, this is partly
due to the fix in r77599, and partly due to the generate-id generating longer
ids in newer versions of xsltproc.

It might be better to improve the id normalisation so that it is more
consistent across versions.
Boostbook: Better error messages from python tests.
Boostbook: Convert more for-each tags to copy-of.
Added support for defaulted and deleted functions in the generated docs. Doxygen 1.8.2 or later needed to generate proper XML for this stylesheet.
Project ids are supposed to be unique. (Refs #5480)
Reflect the role section and simplesect values in the resulting HTML. So that we can style based on types of sections and simplesects. Also add an option to style the labels of sections.. Currently only allowing for removing the parent labels.
Fix boostbook tests for platform inconsistencies.
Fix doxygen test.

For some reason the script is no longer creating an empty cv attribute. Which
appears to be a harmless change.
Add doxygen tests for deleted and default functions. Refs #5480.
Fix doxygen parameter 'formuladir' so that it doesn't need a trailing slash.

Would be nice to fix all uses of directories in a similar manner, but XSL is a
pain.
Add option to permit single depth TOC at chapter level, while maintaining multi-depth TOC at subsequent levels.
This is primarily for the Math lib docs.
Add some C++11 keywords to syntax highlighter.

Quickbook's highlight includes the alternative operator representations (`and`,
and_eq` etc.). They should possibly be added as well.
Normalise space in section class.

Cleans up the output a tad bit when there's no role.
Make adding section's id to their class optional.
Use US-ASCII for single page html.

Same as chunked html. We use ASCII because using UTF-8 can go wrong when a
server is set up to specify another encoding (this does happen). `xsltproc`
will encode all non-ASCII characters as html entities, so nothing will be lost.
[BoostBook] Added support for SVN fixed-length $Date$ keyword.