Improve wording of some REST endpoint descriptions

This makes the descriptions of the REST endpoints more consistent.

Change-Id: I137897270be6815aa0671a11f5b2462d2ddae504
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
diff --git a/Documentation/rest-api-groups.txt b/Documentation/rest-api-groups.txt
index 522cc77..32fd2a5 100644
--- a/Documentation/rest-api-groups.txt
+++ b/Documentation/rest-api-groups.txt
@@ -285,6 +285,8 @@
   "contains all committers for MyProject"
 ----
 
+If the group does not have a description an empty string is returned.
+
 [[set-group-description]]
 PUT /groups/\{group-id\}/description (Set Group Description)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
diff --git a/Documentation/rest-api-projects.txt b/Documentation/rest-api-projects.txt
index 6442892..6919afd 100644
--- a/Documentation/rest-api-projects.txt
+++ b/Documentation/rest-api-projects.txt
@@ -114,6 +114,8 @@
   "Copies to other servers using the Git protocol"
 ----
 
+If the project does not have a description an empty string is returned.
+
 [[set-project-description]]
 PUT /projects/\{project-name\}/description (Set Project Description)
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@@ -150,11 +152,11 @@
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 Deletes the description of a project.
 
-A message to commit the change of the project description can be
-specified in the request body inside a
-link:#project-description-input[ProjectDescriptionInput] entity.
+The request body does not need to include a
+link:#project-description-input[ProjectDescriptionInput] entity if no
+commit message is specified.
 
-Please note, that some proxies prohibit request bodies for DELETE
+Please note that some proxies prohibit request bodies for DELETE
 requests. In this case, if you want to specify a commit message, use
 link:#set-project-description[PUT] to delete the description.
 
@@ -415,9 +417,8 @@
 
 Currently only supported for the `default` dashboard.
 
-A message to commit the deletion of the project dashboard can be
-specified in the request body inside a link:#dashboard-input[
-DashbaordInput] entity.
+The request body does not need to include a link:#dashboard-input[
+DashbaordInput] entity if no commit message is specified.
 
 Please note that some proxies prohibit request bodies for DELETE
 requests.