Merge of #1597. Thanks @czullu

Author: jansenbe

src/sdk/CHANGELOG.md

@@ -33,6 +33,7 @@ The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/).
 - Turned on Rate-Limiting by default with a remaining limit percentage of 10% [jansenbe - Bert Jansen]
 - IRetryEvent.WaitTime will be incorrect when the delay time is greater than 59 seconds #1590 [jansenbe - Bert Jansen]
 - Admin library: TenantProperties: AllowWebPropertyBagUpdateWhenDenyAddAndCustomizePagesIsEnabled #1591 [czullu - Christian Zuellig]
+- Pages - act on general existence of PageTitle-WebPart #1597 [czullu - Christian Zuellig]
 
 ## [1.14]