[DOCS] Adds inference API links to DFA API quick reference (elastic#1323)

Author: szabosteve

Diff for: docs/en/stack/ml/df-analytics/ml-dfanalytics-apis.asciidoc

@@ -18,11 +18,23 @@ The evaluation API endpoint has the following base:
 ----
 // NOTCONSOLE
 
+All the {infer} endpoints have the following base:
+
+[source,js]
+----
+/_ml/inference/
+----
+// NOTCONSOLE
+
+
 * {ref}/put-dfanalytics.html[Create {dfanalytics-jobs}]
 * {ref}/delete-dfanalytics.html[Delete {dfanalytics-jobs}]
 * {ref}/get-dfanalytics.html[Get {dfanalytics-jobs} info]
 * {ref}/get-dfanalytics-stats.html[Get {dfanalytics-jobs} statistics]
 * {ref}/start-dfanalytics.html[Start {dfanalytics-jobs}]
 * {ref}/stop-dfanalytics.html[Stop {dfanalytics-jobs}]
 * {ref}/evaluate-dfanalytics.html[Evaluate {dfanalytics}]
-
+* {ref}/put-inference.html[Create {infer} trained model]
+* {ref}/get-inference.html[Get {infer} trained model]
+* {ref}/get-inference-stats.html[Get {infer} trained model statistics]
+* {ref}/delete-inference.html[Delete {infer} trained model]