Release Memento version 0.1.42.

 * Upgrade `interrupt` to `11.0.0-alpha.25`.
 * Upgrade `avenue` to `0.6.16`.
 * Upgrade `b-tree` to `2.0.0-alpha.115`.
 * Upgrade `amalgamate` to `0.1.73`.
 * Upgrade `constrain` to `2.0.0-alpha.6`.
 * Upgrade `destructible` to `7.0.0-alpha.70`.
 * Upgrade `extant` to `2.0.0-alpha.4`.
 * Upgrade `rescue` to `7.0.0-alpha.18`.
 * Upgrade `journalist` to `0.1.30`.
 * Upgrade `perhaps` to `0.0.12`.

Closes #142.

package.json

@@ -1,6 +1,6 @@
 {
     "name":                 "memento",
-    "version":              "0.1.41",
+    "version":              "0.1.42",
     "description":
 
       "A Paxos backed replicated state machine key-value store.",