Make default merge messages denser.

In particular, make them readable on one line since that's what all the
tools like git-shortlog and gitk end up showing.

git-pull-script

@@ -6,9 +6,7 @@ merge_name=$(echo "$1" | sed 's:\.git/*$::')
 merge_head=HEAD
 if [ "$2" ]
 then
-   merge_name="'$2' branch from
-
-	$merge_name"
+   merge_name="'$2' branch of $merge_name"
    merge_head="refs/heads/$2"
 fi
 

git-resolve-script

@@ -43,7 +43,7 @@ if [ "$common" == "$head" ]; then
 fi
 echo "Trying to merge $merge into $head"
 git-read-tree -u -m $common $head $merge || exit 1
-merge_msg="Merge of $merge_repo"
+merge_msg="Merge $merge_repo"
 result_tree=$(git-write-tree  2> /dev/null)
 if [ $? -ne 0 ]; then
 	echo "Simple merge failed, trying Automatic merge"
@@ -52,7 +52,6 @@ if [ $? -ne 0 ]; then
 		echo "Automatic merge failed, fix up by hand"
 		exit 1
 	fi
-	merge_msg="Automatic merge of $merge_repo"
 	result_tree=$(git-write-tree) || exit 1
 fi
 result_commit=$(echo "$merge_msg" | git-commit-tree $result_tree -p $head -p $merge)