Update sqlstring to 2.2.0

Author: dougwilson

Changes.md

@@ -10,8 +10,9 @@ you spot any mistakes.
   - Used as `cluster.of(...).query(...)`
 * Fix typo in `HANDSHAKE_NO_SSL_SUPPORT` error message #1534
 * Update `bignumber.js` to 2.4.0
-* Update `sqlstring` to 2.1.0
+* Update `sqlstring` to 2.2.0
   - Accept numbers and other value types in `escapeId`
+  - Escape invalid `Date` objects as `NULL`
   - Run `buffer.toString()` through escaping
 
 ## v2.11.1 (2016-06-07)

package.json

@@ -14,7 +14,7 @@
   "dependencies": {
     "bignumber.js": "2.4.0",
     "readable-stream": "1.1.14",
-    "sqlstring": "2.1.0"
+    "sqlstring": "2.2.0"
   },
   "devDependencies": {
     "after": "0.8.2",