Make definition converter more robust.
Merge branch 'master' into math
Allow handlers for setting the actual annotation text.

We use that for shortening link labels and will use it for inline elements.
Extract all available formats for a math formula.
Reimplemented inline-formulas using an annotation based mechanism.

This reduces fragmentation of text elements, as inline formulas are attached
to a plain-text fragment ('{{inline-formula}}').
Support annotated text for reference titles.
Skip whitespaces at the beginning of a paragraph.
Extract an article's submission history as a sequence of dates.
Improved the way how to skip types when parsing annotated text.
Record which footnotes (et others) are used by contributor properties.

These elements should not be processed somewhere else (e.g., extractAuthorNotes).
Fuse extractFootnotes and extractAuthorNotes into extractNotes.
Use a capitalized title for acknowledgment blocks in article info.
Some reordering in converter code.

This is still not very intuitive.
Introduce an extra flag for processing annotated text which makes the default behavior catch all available text.

Before, it stopped on the first unknown element, as it is desired on paragraph level.
Do not claim to have processed corresp in contributor properties.

The corresp element very often contains much more than just an email address.
We could either extend the contributor node to contain everything a corresp
might provide (full-fledged address information), or just leave it as an author-note.
Handle annotated text for inline-formula properly.
Don't create a heading for an empty section.
Allow svg as input format for formulas.

Use this to provide a preview.
Extract a method for annotation post-processing.
Minor cleanup.