ConfigDescriptionParameter: Document step size value 0 to allow any s…

…tep size

Refs openhab/openhab-webui#2832.

Signed-off-by: Florian Hotze <dev@florianhotze.com>

bundles/org.openhab.core.config.core/src/main/java/org/openhab/core/config/core/ConfigDescriptionParameter.java

@@ -265,6 +265,10 @@ public BigDecimal getMaximum() {
     }
 
     /**
+     * Returns the value granularity for a numeric value.
+     * <p>
+     * By setting the step size to <code>0</code>, any granularity is allowed, i.e. any number of decimals is accepted.
+     *
      * @return the value granularity for a numeric value (nullable)
      */
     public BigDecimal getStepSize() {