* Changelog
I hope the current card / log format is flexible enough to accommodate
upcoming changes.

In case a update to the org sources is needed, I'll add a changelog
entry with updating instructions.

** [2020-11-11 Wed]
*** Added
The dashboard now includes a forecast of how many cards will be due
during the next day, week (+7 days) or month (+30 days).
*** Changed
- All dashboard functions were extracted to a separate file
- ~org-fc-stats~ was renamed to ~org-fc-dashboard-stats~
- ~org-fc--hashtable-to-alist~ was renamed to ~org-fc-dashboard--hashtable-to-alist~
- ~org-fc-context-dashboard~ was renamed to ~org-fc-dashboard-context~
- ~org-fc-review-dashboard-context~ was renamed to ~org-fc-dashboard-review~
** [2020-09-09 Wed]
Org-fc now supports nested flashcards.

*** Changed
- It's now possible to mark child headings of flashcards as a flashcards
- When flipping a card, child headings (except the "Back" heading)
  remain collapsed
- Subheadings are ignored when searching for holes of cloze cards
** [2020-07-16 Thu]
*** Changed
- Suspending a card during review now removes all other positions of
  it from the current session, to avoid reviewing suspended cards
** [2020-07-08 Wed]
*** Changed
The awk index now also includes the headline text of each card.

This will be useful for building a ~tabulated-list-mode~ based card
overview.
** [2020-07-06 Mon]
*** Added
- ~org-fc-suspend-tree~ for suspending all cards in a subtree
*** Changed
- unsuspending overdue cards doesn't reset their review data anymore
** [2020-07-04 Sat]
*** Added
- ~org-fc-review-edit~ (bound to ~p~) pauses the review for editing
  the current card. A new mode ~org-fc-review-edit-mode~ adds
  keybindings for resuming & quitting the review.
** [2020-07-03 Fri]
*** Changed
- By default, failed cards are appended to the end of the review session.
  This can be configured via ~org-fc-append-failed-cards~
- ~org-fc-map-cards~ takes an optional ~scope~ argument,
  similar to ~org-map-entries~.
*** Added
- ~org-fc-unsuspend-tree~ unsuspends all cards in the subtree at point
** [2020-07-02 Thu]
*** Changed
- ~org-fc-review-rate-card~ was renamed to ~org-fc-review-rate~
** [2020-07-01 Wed]
*** Changed
- The review history file is only written once per review,
  as a first step towards implementing a "undo-rating" command
** [2020-06-29 Mon]
*** Added
- Shuffling of positions for the review can be disabled
  by setting ~org-fc-shuffle-positions~ to ~nil~
*** Changed
- Error messages from shell commands are promoted
** [2020-06-28 Sun]
*** Added
- ~org-fc-before-review-hook~ that runs when a review session is started
** [2020-06-26 Fri]
*** Changed
- Messages are not inhibited during review
- Whitelisted drawers are expanded during review
*** Added
- A ~org-fc-after-review-hook~ that runs when the review ends / is quit
- ~org-fc-keymap-hint~ extension
- ~org-fc-audio~ extension
** [2020-06-25 Thu]
*** Added
- ~SCHEDULED: ...~, ~DEADLINE: ...~ timestamps are hidden during
  review
- Drawers in ~org-fc-drawer-whitelist~ are not hidden during review
*** Changed
- During the review process, two minor modes are used instead of two
  hydras
** [2020-05-24 Sun]
*** Changed
- Include file information in card index
- Maintain order of positions in a card when shuffling
** [2020-05-22 Fri]
*** Changed
- Exit hydra when review is started
** [2020-05-08 Fri]
*** Changed
- Per-context dashboard
- Improve org-indent of cards
- Use special "fc-demo" tag for demo cards
- Move opening of flip/rating hydras to main review loop
** [2020-05-01 Fri]
*** Internal
The AWK scripts now generate S-expressions instead of CSV tables, this
way ~read~ can be used to parse the data instead of relying on a set
of custom parsing functions.

This also allows passing more complex data structures from AWK to
org-fc.
** [2020-04-29 Wed]
Implemented a new version of the spacing algorithm (SM2) that's used
by org-fc.

The only difference is in how the next interval for cards rated as
"hard" is calculate.

The initial version (~'sm2-v1~) would decrease the ease factor by
0.15, then calculate the next interval by multiplying the previous
interval with the new ease factor.

In the new version (~'sm2-v2~), the interval is always multiplied by a
factor of 1.2, similar to the version of SM2 used by Anki.

~org-fc-algorithm~ can be used to set which version of the
algorithm should be used, defaulting to ~'sm2-v1~.

Once I have evaluated the performance of the new algorithm,
the default version will change to ~'sm2-v2~.
** [2020-04-12 Sun]
*** Added
- =text-input= card type
** [2020-02-08 Sat]
*** Changed
- Add a "Z" suffix to all ISO8601 timestamps
*** Added
- A function to estimate the number of reviews in the next n days
** [2020-02-03 Mon]
*** Internal
- ~org-fc-due-positions-for-paths~ now shuffles the lists of positions
  using an Emacs Lisp function instead of depending on =shuf=
- All awk-indexer functions now use ~gawk~ instead of ~awk~