Cleanup the command line tool index page

Use sections of the different classes of tools, making the outline
much more useful.  Also mentioned the link to determine the proper
port number for Gerrit.

Change-Id: I16c10074c7d420baa38a3e739b69e5bcbbd1509a
Signed-off-by: Shawn O. Pearce <sop@google.com>
1 file changed