preen ondrej's hash table notes

Data-structure-survey.md

@@ -126,13 +126,21 @@ Case-sensitive and case-insensitive variants, chosen at run-time.
 Uses chaining, so it is heavy on indirection and heavy on allocation.
 Modern hash tables use open addressing.
 
-Ondrej: there's work to do on the isc_ht:
+## Ondřej's notes
 
-1. make header-only variant of the hashtable, so we can unify the usage across the codebase (e.g. no extra allocations when storing item)
+There's work to do on `isc/ht`:
-2. there's a branch, where I implemented robin-hood hashing, but I never finished because of 1), the branch is ondrej/robin-hood-unordered-node-map
+
-3. the resizing was added only recently, we still miss shrinking (should be easy enough to do)
+ 1. make header-only variant of the hashtable, so we can unify the usage
+    across the codebase (e.g. no extra allocations when storing item)
+
+ 2. there's a branch, where I implemented robin-hood hashing, but I never
+    finished because of 1), the branch is ondrej/robin-hood-unordered-node-map
+
+ 3. the resizing was added only recently, we still miss shrinking (should be
+    easy enough to do)
+
+`dns/adb` was recently refactored, it used a custom hashtable before
 
-Ondrej: dns_adb was recently refactored, it used a custom hashtable before
 
 # `isc/pool`