Updated changelog for upcoming 5.1.3 release

CHANGES

@@ -1,3 +1,28 @@
+Version 5.1.3
+(released 09 Apr 2021)
+
+Fixed GitHub issues in this release:
+
+  * #2159 ([BUG] UPS widget is inconsistent between showing minutes and
+           seconds remaining time)
+  * #2240 ([BUG] Workaround for wrong interface speed SNMP
+           implementations)
+  * #2253 (Drastically improve page load times on maintenance edit form)
+  * #2254 ([BUG] Search after partial IP-address crashes)
+  * #2255 (ipdevinfo maintenance task link should be to task details
+           view, not the task editor)
+  * #2257 (Exclude Coriant Groove port sensors from collection based on
+           portAdminStatus)
+  * #2260 (IP Device custom data should be "urlized")
+  * #2263 ([BUG] Job 'inventory' for xxx aborted: Job aborted due to
+           save failure (cause=ValueError('A string literal cannot
+           contain NUL (0x00) characters.')))
+  * #2264 (Hardcoded vendor name)
+  * #2267 (Link to filtered report must be urlencoded)
+  * #2269 ([BUG] ipdevinfo shows empty Function-field for some hosts)
+  * #2270 ([BUG] Documentation search does not work)
+  * #2275 (SshChecker not handling connections properly)
+
 Version 5.1.2
 (released 15 Jan 2021)