Previously it could fail to generate an index if the processing of the
final file set "Inserted" or "Deleted" to FALSE, even if a prior file
had set it to TRUE

hmmlib: -std=gnu99

HTML-santitise episode title and project name from templates. This won't
always be correct, but I reckon the common case will require it.

This lets users of Firefox 59+ get sub-millisecond accurate performance:
https://developer.mozilla.org/en-US/docs/Web/API/Performance/now

Don't \-escape anything in the index

Document server's security header (recommended) requirements

We no longer prevent enforcement of strict server security policies (to
be documented)

Add bounds-checking to the Copy string functions, fixing buffer sizes

Fix the marker skipping (e.g. :afk)

Different ISBN database, and slightly more flexible BuildReference()
Permit line-breaking on '/' in the references menu

cinera.css and cinera_player*.js:
More subtle "click here to regain focus" - for @insofaras
Persist theatre mode - for @insofaras
Resume in-progress video at previous timecode - for @AsafGartner

It treats co-hosts and guests differently from chat commenters, styling
and categorising annotations for them such that their contributions
don't come under the "Chat comment" medium

Also do some essentially cosmetic code compression of the marker cases
and other things

cinera_player_pre.js: Make the credits menu initially focus the host's
person if they have no support, rather than the first credited person
who has support

It merely checks the video's privacy status and, if not public, records
its corresponding HMML base filename privately in the .metadata without
generating a player page or a search / table of contents entry for it.
Every four hours it will loop over the .metadata to recheck the privacy
status of any privately recorded entries, and process newly public ones.

Fix template validation to check that the script comes after both the
player and menus (previously it only specified the player).

Fix relocation code to try and remove only the child directories of the
BaseDir, and no shallower (previously it would try and "recursively"
remove directories all the way back to /, obviously not actually getting
there because it would encounter a non-empty directory along the way).

Add "Modes" to the startup printout.

Flags:
    -g Ignore privacy status

Also optimise out superfluous searches, and relieve IndexToBuffer() of
the need to string-search the .index

Rewrite the table of contents page after deleting an entry

This commit also retains profiling, as a reminder to me how I used it,
and the old linear search code. The timing blocks and the old code may
be deleted in a future commit

Essentially, the previous change prevented the marker progress code from
firing if the user only interacts with the YouTube player directly.

cinera.c: Try to curl the quotes in, rather than straight up deleting
them, if(ShouldFetchQuotes)

cinera_player_pre.js: Episode keyboard navigation. Also swap out A for
K, and D for J
cinera_player_pre.js: Handle the case in onRefChanged() in which the
filter_container or filterState is not present
cinera.c: Refetch quotes when processing a set of annotations >60 mins
after the last fetch

Flags:
    -w Force quote cache rebuild

Also compress the template code

cinera_player_pre.js: Fix bug in which onRefChanged() tried to call
player.jumpToNextMarker(); before the player was ready. This could
happen if its first marker's timecode is 0:00 and medium is :afk

Enable Theatre mode to work in containers styled with max-width or
max-height

Also fix the inotify loop, augment the index (the .metadata files) to
contain data useful for insobot, and futureproof UpgradeDB()

Flags:

    * -e Examine Index
        Just pop an -e on the end of your usual list of flags
    * -u Update Interval (was -U)