Update licensing; fix screenshots; edit generally

Author: marciw

docs/reference/data-streams/logs.asciidoc

@@ -115,8 +115,8 @@ Index mode supports the following values:
 
 `time_series`::: Index mode optimized for storage of metrics documented in <<tsds-index-settings,TSDS Settings>>.
 
-`logsdb`::: Index mode optimized for storage of logs. It applies default sort settings on the `hostname` and `timestamp` fields and uses <<synthetic-source,synthetic `_source`>>. <<index-modules-index-sorting,Index sorting>> on different fields is still allowed.
-preview:[]
+`logsdb`::: _(https://www.elastic.co/pricing[Enterprise subscription] required)_ +
+Index mode optimized for storage of logs. It applies default sort settings on the `hostname` and `timestamp` fields and uses <<synthetic-source,synthetic `_source`>>. <<index-modules-index-sorting,Index sorting>> on different fields is still allowed.
 
 [[routing-partition-size]] `index.routing_partition_size`::
 

docs/reference/images/index-mgmt/management-data-stream-fields.png

@@ -67,7 +67,7 @@ This value is the time period for which your data is guaranteed to be stored. Da
 Elasticsearch at a later time.
 
 [role="screenshot"]
-image::images/index-mgmt/management-data-stream.png[Data stream details]
+image::images/index-mgmt/management-data-stream-fields.png[Data stream details]
 
 * To view more information about a data stream, such as its generation or its
 current index lifecycle policy, click the stream's name. From this view, you can navigate to *Discover* to

docs/reference/images/index-mgmt/management-data-stream.png

@@ -44,6 +44,7 @@ DELETE _index_template/template_*
 * If the {es} {security-features} are enabled, you must have the
 `manage_index_templates` or `manage` <<privileges-list-cluster,cluster
 privilege>> to use this API.
+* The `logsDB` index mode requires an https://www.elastic.co/pricing[Enterprise subscription].
 
 [[put-index-template-api-desc]]
 ==== {api-description-title}
@@ -115,10 +116,10 @@ See <<create-index-template,create an index template>>.
 
 `index_mode`::
 (Optional, string) Type of data stream to create. Valid values are `null`
-(regular data stream) and `time_series` (<<tsds,time series data stream>>).
+(standard data stream), `time_series` (<<tsds,time series data stream>>) and `logsdb` 
+(<<logs-data-stream,logs data stream>>, which requires an https://www.elastic.co/pricing[Enterprise subscription]).
 +
-If `time_series`, each backing index has an `index.mode` index setting of
-`time_series`.
+The template's `index_mode` sets the `index.mode` of the backing index.
 =====
 
 `index_patterns`::

docs/reference/images/index-mgmt/management-index-templates.png

@@ -1,12 +1,7 @@
 [[synthetic-source]]
 ==== Synthetic `_source`
 
-IMPORTANT: Synthetic `_source` is Generally Available only for TSDB indices
-(indices that have `index.mode` set to `time_series`). For other indices,
-synthetic `_source` is in technical preview. Features in technical preview may
-be changed or removed in a future release. Elastic will work to fix
-any issues, but features in technical preview are not subject to the support SLA
-of official GA features.
+IMPORTANT: This feature requires an https://www.elastic.co/pricing[Enterprise subscription].
 
 Though very handy to have around, the source field takes up a significant amount
 of space on disk. Instead of storing source documents on disk exactly as you