Mostly changes the layout to no longer use position:absolute.
Instead, flexbox is used to arrange rows of buttons, as well as the central menu column.

Whenever a collectible is unlocked in-game, a pulsing indicator button will appear
above the player's info tab.

Clicking this will pull up a modal dialog displaying basic info on what was just collected.

Collectibles can now have an optional <counter> subelement, specifying a counter
value that must be reached before a collectible can be unlocked.

Collectible counters work in exactly the same way as marker counters,
and support roughly the same set of operations (increment, decrement, set, and unlock).

To support this, <state> elements now have a `collectible-value` attribute in
addition to a `collectible` attribute, to specify values for incrementing,
decrementing, or setting collectible counters:

 - Numbers prefixed with '+' will be interpreted as 'increment counter' commands.
   (i.e. '+5' = increment by 5, '+1' = increment by 1)
 - Numbers prefixed with '-' will be interpreted as 'decrement counter' commands.
   (i.e. '-5' = decrement by 5, '-1' = decrement by 1)
 - Unprefixed numbers will be interpreted as 'set counter' commands.
   (i.e. '5' = set to 5, '1' = set to 1).

Note that counter values are always >= 0.
If a `collectible-value` attribute is not specified, the default action is to
unlock the specified collectible, setting any attached counter to its maximum value.

Meia/Revy Line Tweaks

See merge request spnati/spnati.gitlab.io!1489

Florina Easter Alt

See merge request spnati/spnati.gitlab.io!1488

Character Editor 4.1

See merge request spnati/spnati.gitlab.io!1486

Pose Engine - Ease across entire animation rather than frame-to-frame

See merge request spnati/spnati.gitlab.io!1487

Sponsorship Updates

See merge request spnati/spnati.gitlab.io!1485

Padded out Masturbation responses.

Typo fix and Miko/Mavis responses. Scarlet Devil Mansion now explodes during the epilogue. Figuratively. Offscreen. Without being mentioned in any way, shape or form.

Ryuko Conditional Line Update

See merge request spnati/spnati.gitlab.io!1484

Changes blank images, fixes a test case