bash completion: Append space after file names have been completed

When completing `git show origin/maint:Makef<tab>` we should add a
space after the filename has been completed, so that the user can
immediately begin the next argument.

I also added a special case for the symlink variant so we treat it
just like a normal blob, as there are no items below it in the Git
tree structure.
Signed-off-by: NShawn O. Pearce <spearce@spearce.org>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

contrib/completion/git-completion.bash

@@ -294,9 +294,17 @@ __git_complete_file ()
 			ls="$ref"
 			;;
 	    esac
+		local IFS=$'\n'
 		COMPREPLY=($(compgen -P "$pfx" \
 			-W "$(git --git-dir="$(__gitdir)" ls-tree "$ls" \
-				| sed '/^100... blob /s,^.*	,,
+				| sed '/^100... blob /{
+				           s,^.*	,,
+				           s,$, ,
+				       }
+				       /^120000 blob /{
+				           s,^.*	,,
+				           s,$, ,
+				       }
 				       /^040000 tree /{
 				           s,^.*	,,
 				           s,$,/,