puzzles: add Slide and Sokoban.

This enables two of the "unfinished" puzzles. Slide requires a new "sticky
mouse mode" to enable dragging. The help system is disabled for these
puzzles, since they lack manual chapters.

Group is currently unplayable due to lack of request_keys() support, which
will need to be added upstream. Separate fails to draw anything.

Change-Id: I7bcff3679ac5b10b0f39c5eaa19a36b4b1fe8d53

1 files changed, 14 insertions, 0 deletions

diff --git a/apps/plugins/puzzles/src/unfinished/README b/apps/plugins/puzzles/src/unfinished/README
new file mode 100644
index 0000000000..c96ccc935a
--- /dev/null
+++ b/apps/plugins/puzzles/src/unfinished/README
@@ -0,0 +1,14 @@
+This subdirectory contains puzzle implementations which are
+half-written, fundamentally flawed, or in other ways unready to be
+shipped as part of the polished Puzzles collection.
+
+The CMake build system will _build_ all of the source in this
+directory (to ensure it hasn't become unbuildable), but they won't be
+included in all-in-one puzzle binaries or installed by 'make install'
+targets. If you want to temporarily change that, you can reconfigure
+your build by defining the CMake variable PUZZLES_ENABLE_UNFINISHED.
+For example,
+
+  cmake . -DPUZZLES_ENABLE_UNFINISHED="group;slide"
+
+will build as if both Group and Slide were fully official puzzles.