Fix clone with commit-msg hook when project name contains '/'

Cloning a project 'foo/bar' with

  git clone ssh://<user>@<host>:29418/foo/bar

clones the project into a 'bar' folder.

This means that the commit-msg hook needs to be copied into
'bar/.git/hooks/', but so far the command tried to copy it into
'foo/bar/.git/hooks/' which failed since the folder didn't exist.

The clone commands that are returned from the GetServerInfo REST
endpoint may now contain 2 placeholders, '${project}' for the project
name and '${project-base-name}' for the project base name. E.g. for a
project 'foo/bar' '${project}' is a placeholder for 'foo/bar' and
'${project-base-name}' is a placeholder for 'bar'.

Bug: Issue 3444
Change-Id: Ia2dd9a70063498bdf21ecd66f2d25779515dd6d5
Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>
diff --git a/Documentation/rest-api-config.txt b/Documentation/rest-api-config.txt
index d8a6dba..88aec2e 100644
--- a/Documentation/rest-api-config.txt
+++ b/Documentation/rest-api-config.txt
@@ -1120,7 +1120,10 @@
 |`clone_commands`    ||
 Clone commands as a map which maps the command name to the clone
 command. In the clone command '${project}' is used as
-placeholder for the project name.
+placeholder for the project name and '${project-base-name}' as name
+for the project base name (e.g. for a project 'foo/bar' '${project}'
+is a placeholder for 'foo/bar' and '${project-base-name}' is a
+placeholder for 'bar').
 
 Empty, if accessed anonymously and the download scheme requires
 authentication.