Document removals of deprecated transport settings

This commit udpates the plugin docs to indicate the removal of deprecated
setting. This includes the version the deprecation appeared in as well as the
version the removal landed in.

docs/index.asciidoc

@@ -478,6 +478,8 @@ Enable SSL/TLS secured communication to Elasticsearch cluster.
 Leaving this unspecified will use whatever scheme is specified in the URLs listed in <<plugins-{type}s-{plugin}-hosts>> or extracted from the <<plugins-{type}s-{plugin}-cloud_id>>.
 If no explicit protocol is specified plain HTTP will be used.
 
+When not explicitly set, SSL will be automatically enabled if any of the specified hosts use HTTPS.
+
 [id="plugins-{type}s-{plugin}-ssl_key"]
 ===== `ssl_key`
   * Value type is <<path,path>>
@@ -608,12 +610,12 @@ option when authenticating to the Elasticsearch server. If set to an
 empty string authentication will be disabled.
 
 
-[id="plugins-{type}s-{plugin}-deprecated-options"]
-==== Elasticsearch Input deprecated configuration options
+[id="plugins-{type}s-{plugin}-removed-options"]
+==== Elasticsearch Input Removed configuration options
 
-This plugin supports the following deprecated configurations.
+The following configurations will be removed in version 5.0.0.
 
-WARNING: Deprecated options are subject to removal in future releases.
+WARNING: These options have been deprecated and will be removed in version 5.0.0. Please use their replacements instead.
 
 [cols="<,<,<",options="header",]
 |=======================================================================
@@ -625,7 +627,9 @@ WARNING: Deprecated options are subject to removal in future releases.
 
 [id="plugins-{type}s-{plugin}-ca_file"]
 ===== `ca_file`
-deprecated[4.17.0, Replaced by <<plugins-{type}s-{plugin}-ssl_certificate_authorities>>]
+deprecated[4.17.0, Will be removed in 5.0.0, replaced by <<plugins-{type}s-{plugin}-ssl_certificate_authorities>>]
+
+This setting will be removed in 5.0.0. Please use <<plugins-{type}s-{plugin}-ssl_certificate_authorities>> instead.
 
 * Value type is <<path,path>>
 * There is no default value for this setting.
@@ -634,7 +638,9 @@ SSL Certificate Authority file in PEM encoded format, must also include any chai
 
 [id="plugins-{type}s-{plugin}-ssl"]
 ===== `ssl`
-deprecated[4.17.0, Replaced by <<plugins-{type}s-{plugin}-ssl_enabled>>]
+deprecated[4.17.0, Will be removed in 5.0.0, replaced by <<plugins-{type}s-{plugin}-ssl_enabled>>]
+
+This setting will be removed in 5.0.0. Please use <<plugins-{type}s-{plugin}-ssl_enabled>> instead.
 
 * Value type is <<boolean,boolean>>
 * Default value is `false`
@@ -645,7 +651,10 @@ server (i.e. HTTPS will be used instead of plain HTTP).
 
 [id="plugins-{type}s-{plugin}-ssl_certificate_verification"]
 ===== `ssl_certificate_verification`
-deprecated[4.17.0, Replaced by <<plugins-{type}s-{plugin}-ssl_verification_mode>>]
+deprecated[4.17.0, Will be removed in 5.0.0, replaced by <<plugins-{type}s-{plugin}-ssl_verification_mode>>]
+
+This setting will be removed in 5.0.0. Please use <<plugins-{type}s-{plugin}-ssl_verification_mode>> instead.
+
 
 * Value type is <<boolean,boolean>>
 * Default value is `true`