contrib/git-svn: better documenting of CLI switches

Also, fix a asciidoc formatting error

Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
diff --git a/contrib/git-svn/git-svn.txt b/contrib/git-svn/git-svn.txt
index 7306048..8e9a971 100644
--- a/contrib/git-svn/git-svn.txt
+++ b/contrib/git-svn/git-svn.txt
@@ -116,6 +116,8 @@
 	They are both passed directly to git-diff-tree see
 	git-diff-tree(1) for more information.
 
+ADVANCED OPTIONS
+----------------
 -b<refname>::
 --branch <refname>::
 	Used with 'fetch' or 'commit'.
@@ -131,8 +133,21 @@
 	This option may be specified multiple times, once for each
 	branch.
 
+-i<GIT_SVN_ID>::
+--id <GIT_SVN_ID>::
+	This sets GIT_SVN_ID (instead of using the environment).  See
+	the section on "Tracking Multiple Repositories or Branches" for
+	more information on using GIT_SVN_ID.
+
 COMPATIBILITY OPTIONS
 ---------------------
+--upgrade::
+	Only used with the 'rebuild' command.
+
+	Run this if you used an old version of git-svn that used
+	'git-svn-HEAD' instead of 'remotes/git-svn' as the branch
+	for tracking the remote.
+
 --no-ignore-externals::
 	Only used with the 'fetch' and 'rebuild' command.
 
@@ -177,7 +192,7 @@
 	git-svn commit remotes/git-svn..my-branch
 # Something is committed to SVN, pull the latest into your branch::
 	git-svn fetch && git pull . remotes/git-svn
-# Append svn:ignore settings to the default git exclude file:
+# Append svn:ignore settings to the default git exclude file::
 	git-svn show-ignore >> .git/info/exclude
 
 DESIGN PHILOSOPHY