Create child data node (part 1): CPS service + REST

Issue-ID: CPS-337
Change-Id: I9c5c62d144b5301ac80e2b82a5cc66a980dad011
Signed-off-by: Ruslan Kashapov <ruslan.kashapov@pantheon.tech>
diff --git a/cps-rest/docs/api/swagger/cpsData.yml b/cps-rest/docs/api/swagger/cpsData.yml
index 2464489..54c8966 100755
--- a/cps-rest/docs/api/swagger/cpsData.yml
+++ b/cps-rest/docs/api/swagger/cpsData.yml
@@ -33,6 +33,7 @@
     parameters:
       - $ref: 'components.yml#/components/parameters/dataspaceNameInPath'
       - $ref: 'components.yml#/components/parameters/anchorNameInPath'
+      - $ref: 'components.yml#/components/parameters/xpathInQuery'
     requestBody:
       required: true
       content: