WCAG2.0-compliant luminosity contrast for <code>

#ff4500 has luminosity contrast of 3.4:1. Need at least 4.5:1. Use #dc3b00.
WCAG2.0-compliant contrast on colour for <code>

#DC3B00 provides contrast of 4.5:1 on white. But to provide a little flexibility, e.g. in the case that some <code> is in a <th> with background #eee, a colour of #C83500 provides 4.56:1 contrast, while still standing out as red text.
Allow references that are missing href.
Detection of missing abstract was broken
make shortName not be required for basic documents
new build
v3.2.15
Support Previous Version on NOTEs

As per a discussion on spec-prod, NOTEs can have Previous Versions, so we need to support output of that header too.
Allow permalink on div with an h* element
Test to ensure permalinks are on h* within div
Merge pull request #319 from halindrome/patch-2

Support Previous Version on NOTEs
Merge pull request #310 from tobie/fix-refs

Allow references that are missing href.
Merge pull request #307 from jasonkiss/develop

More accessible luminosity contrast on colour for <code>
Merge pull request #320 from halindrome/patch-3

Adding permalinks to h* within div
v3.2.16
Don't break NOTES that have no previous version
v3.2.17
add support for Process picking
v3.2.18
overwrite from develop