[DOCS] Adds list of supported functions to jobs-from-visualizations guide (elastic#2209)

Author: szabosteve

docs/en/stack/ml/anomaly-detection/ml-jobs-from-visuals.asciidoc

@@ -9,15 +9,26 @@ You can create {anomaly-jobs} from the compatible Lens charts on **Dashboard**.
 
 [discrete]
 [[prereqs]]
-== Prerequisites
+== Prerequisites and limitations
 
 * Only chart-like visualizations are compatible. Supported chart types are 
 `area`, `area_percentage_stacked`, `area_stacked`, `bar`, `bar_horizontal`, 
 `bar_horizontal_stacked`, `bar_percentage_stacked`, `bar_stacked`, and `line`.
 
+* Supported {anomaly-detect} functions are `average`, `count`, `max`, `median`, 
+`min`, `sum`, `unique_count`.
+
 * The chart must contain a date field on one axis and it must be the same as the 
 default date field for the {data-source}.
 
+* In case of a multi-layered chart, only the compatible layers can be used to 
+create an {anomaly-job}.
+
+* Chart layers which contain a field that uses a
+{kibana-ref}/create-a-dashboard-of-panels-with-ecommerce-data.html#compare-time-ranges[time shift] 
+or a field that has a `filter by` setting applied cannot be used to create an 
+{anomaly-job}.
+
 
 [discrete]
 [[create-job]]
@@ -29,7 +40,6 @@ NOTE: You need to have a compatible visualization on **Dashboard** to create an
 which is based on the {kib} sample flight data set. Select the `Flight count` 
 visualization from the dashboard.
 
-
 . Go to **Analytics > Dashboard** and select a dashboard with a compatible 
 visualization.
 . Open the **Options (...) menu** for the panel, then select **More**.  
@@ -51,8 +61,8 @@ field, the multi metric job wizard is used for creating the job. For a single
 metric chart, the single metric wizard is used.
 
 If the configured time range of the chart is relative, it is converted to 
-absolute start and end times in the job configuration. If the conversion of these times 
-fails, the whole time range from the index is used.
+absolute start and end times in the job configuration. If the conversion of 
+these times fails, the whole time range from the index is used.
 
 
 [discrete]