Add --limit option to docker search

This fix tries to address the issue raised in #23055.
Currently `docker search` result caps at 25 and there is
no way to allow getting more results (if exist).

This fix adds the flag `--limit` so that it is possible
to return more results from the `docker search`.

Related documentation has been updated.

Additional tests have been added to cover the changes.

This fix fixes #23055.

Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

man/docker-search.1.md

@@ -8,6 +8,7 @@ docker-search - Search the Docker Hub for images
 **docker search**
 [**-f**|**--filter**[=*[]*]]
 [**--help**]
+[**--limit**[=*LIMIT*]]
 [**--no-trunc**]
 TERM
 
@@ -30,6 +31,9 @@ of stars awarded, whether the image is official, and whether it is automated.
 **--help**
   Print usage statement
 
+**--limit**=*LIMIT*
+  Maximum returned search results. The default is 25.
+
 **--no-trunc**=*true*|*false*
    Don't truncate output. The default is *false*.