Timerserver interval can be set as a float in case shorter than 1 second interva…

…l for activities is needed.

/reviewed-on nexedi/slapos!281

software/erp5/instance-erp5-input-schema.json

@@ -117,7 +117,7 @@
             "timerserver-interval": {
               "description": "Timerserver tick perdiod, in seconds, or 0 to disable",
               "default": 5,
-              "type": "integer"
+              "type": "number"
             },
             "ssl-authentication": {
               "title": "Enable SSL Client authentication on this zope instance.",