Filter changesNotifications by doc/revision number -fix 0ct22 (#79)

final version of  filtering  by  doc/rev

Author: groezing

package.json

@@ -9,6 +9,7 @@
     "moment": "^2.11.1",
     "lodash": "^4.17.13",
     "needle": "^3.1.0",
+    "lru-cache": "^7.9.0",
     "@cloudant/cloudant": "4.2.4",
     "nano": "8.2.1",
     "json-stringify-safe": "^5.0.1",