build: migrate from Cask to Eask

Cask's upstream has slowed. Eask is the actively maintained successor.

Eask's `package-file` directive doesn't auto-install the deps from the .el header's Package-Requires, so the Eask file mirrors emacs/seq/org/persist explicitly. `eask install-deps` also doesn't pull transitive deps, so dash, m-buffer, and shut-up needed their own `depends-on` lines for undercover and elisp-lint to activate.

The Makefile swaps are mechanical: $(CASK) → $(EASK), `cask install` → `eask install-deps --dev`, `cask build` → `eask compile`.

The URL in org-drill.el's header pointed at the abandoned upstream's GitLab issues page. Eask cross-validates that against website-url, so I updated it to the GitHub mirror — where users file issues now.

1 files changed, 33 insertions, 0 deletions

diff --git a/Eask b/Eask
new file mode 100644
index 0000000..215a816
--- /dev/null
+++ b/Eask
@@ -0,0 +1,33 @@
+;; -*- mode: eask; lexical-binding: t -*-
+
+(package "org-drill"
+         "2.7.0"
+         "Self-testing using spaced repetition")
+
+(website-url "https://github.com/cjennings/org-drill")
+(keywords "games" "outlines" "multimedia")
+
+(package-file "org-drill.el")
+
+(source "gnu")
+(source "nongnu")
+(source "melpa")
+(source "org")
+
+(depends-on "emacs" "25.3")
+(depends-on "seq" "2.14")
+(depends-on "org" "9.6")
+(depends-on "persist" "0.3")
+
+(development
+ (depends-on "assess")
+ (depends-on "undercover")
+ (depends-on "package-lint")
+ (depends-on "elisp-lint")
+ ;; Transitive deps that Eask doesn't auto-install:
+ ;;   dash      ← undercover, elisp-lint
+ ;;   m-buffer  ← assess
+ ;;   shut-up   ← undercover
+ (depends-on "dash")
+ (depends-on "m-buffer")
+ (depends-on "shut-up"))