This commit adds a button at the top of the TOC
headings list called "Expand all". This will expand
all of the subheadings in the list for easier searching.
Clicking the button again will hide all the subheadings except
the currently active one.
* FEATURE: Allow TOC for replies
This commit adds an optional setting that allows enabling a TOC for
replies. TOCs for replies are not affected by autoTOC settings like
`auto_TOC_tags` and must be inserted manually.
Martin Brennan
锦心
Jarek Radosz
Kris