Remove unreachable old file admin/error.jsp (NMS-6147)

Conflicts:
	opennms-webapp/src/main/webapp/admin/error.jsp
NMS-6168 - maint_events.sh is not working
Merge remote-tracking branch 'origin/1.10' into 1.12
Fix misnamed method SyslogDestination.setMaxMessageLength(int)
NMS-6129 handle rate limits cleanly in the geo maps
NMS-6046 Honor JVM's HTTP proxy settings (http.proxyHost/http.proxyPort) when geocoding
Fixing Eclipse m2e issues on integrations/opennms-jasper-extensions
Merge remote-tracking branch 'origin/1.12' into space/13.2

Conflicts:
	features/geocoder/google/pom.xml
	features/vaadin-node-maps/src/main/java/org/opennms/features/vaadin/nodemaps/internal/MapWidgetComponent.java