Make "git clone" a lot more user-friendly

This silently adds the ".git" directory component if needed, so you
don't need to state it explicitly for the source.  Also, it turns the
source into an absolute pathname when local, so that you can use
relative pathnames without losing sight of the source when we cd into
the destination.

git-clone-script

@@ -10,6 +10,10 @@ usage() {
 	exit 1
 }
 
+get_repo_base() {
+	(cd "$1" && (cd .git ; pwd)) 2> /dev/null
+}
+
 use_local=no
 while
 	case "$#,$1" in
@@ -22,7 +26,15 @@ do
 	shift
 done
 
+# Turn the source into an absolute path if
+# it is local
 repo="$1"
+local=no
+if base=$(get_repo_base "$repo"); then
+	repo="$base"
+	local=yes
+fi
+
 dir="$2"
 mkdir "$dir" &&
 D=$(
@@ -31,8 +43,8 @@ D=$(
 test -d "$D" || usage
 
 # We do local magic only when the user tells us to.
-case "$use_local" in
-yes)
+case "$local,$use_local" in
+yes,yes)
 	( cd "$repo/objects" ) || {
 		repo="$repo/.git"
 		( cd "$repo/objects" ) || {