[Sitemap] Remove duplicate sentence (openhab#747)

Signed-off-by: Thomas Dietrich <thomas.dietrich@tu-ilmenau.de> (github: ThomDietrich)

configuration/sitemaps.md

@@ -544,10 +544,13 @@ visibility=[item_name operator value, item_name operator value, ... ]
 ```
 
 Valid comparison operators are:
+
 - equal to `==`, unequal to `!=`
 - less than or equal to `<=`, greater than or equal to`>=`
 - less than `<`, greater than `>`
+
 Expressions are evaluated from left to right.
+The Item will be visible if any one of the comparisons is evaluated as `true`, otherwise it will be hidden.
 
 **Examples:**
 
@@ -557,14 +560,9 @@ visibility=[TV_Power==ON]
 visibility=[Day_Time=="Morning", Day_Time=="Afternoon", Temperature>19]
 ```
 
-If any one of the comparisons is evaluated as `true`, the Item will be visible, otherwise it will be hidden.
-It is important to note that visibility may be determined based on only one condition at a time.
-If any one of the comparisons is evaluated as `true`, then the Item will be visible.
-Otherwise it will be hidden.
-
 In the third example above, a control for a lawn sprinkler will be visible if it is Morning, *OR* if it is Afternoon, *OR* if the temperature is above 19 °C.
 Combining multiple conditions, for example Morning *AND* above 19 °C is not supported.
-To control visibility based upon combining multiple Items, or on more complex conditions, consider defining and using an additional Item that is set by a Rule.
+To control visibility based upon combining multiple Items, or on more complex conditions, consider defining and using an additional intermediate Item that is set by a Rule.
 Rules have a rich set of features that can support more involved scenarios.
 
 ### Label and Value Colors