Fixes to git debug system conditional imports
Add --nogit option for speedier debugging
Change all regression tests to use --nogit for speed
Fix for regression test 004
Add --nogit option to nlmprocessor
Add --nogit option to debug init (nlmprocessor)
Add --nogit option to referencelinker
Further optimisation of --nogit
Initial empty title, bold sibling infrastructure
Fixes to empty title, bold sibling infrastructure to pass regression tests
Allow TEI input option

Also minor fix to regression tests
Further regression test fixes to bold classifier
Regression tests for strangely bolded titles
Compliance enforcement structure for mis-nested xref links
Regression test document for xref/ext-link nested compliance
Regression test for nested xref/ext-link compliance
Additional compliance enforcement on unlinked xref items
Additional compliance for figure captions
Further unparseable image compliance
Update README information with latest usage options

NB this commit was made (and pushed!) on board a plane.