Fixed 2 bashism and now works on bash and dash

bin/git-effort

@@ -73,8 +73,9 @@ effort() {
     len=${#file}
     dot="."
     f_dot=$file
-    for ((i=0; i < 45-$len ;i++)); do
+    i=0 ; while test $i -lt $((45-$len)) ; do
        f_dot=$f_dot$dot
+       i=$(($i+1))
     done
 
     printf "  \033[${color}m%s %-10d" $f_dot $commits
@@ -116,7 +117,11 @@ fi
 
 # [file ...]
 
-files=${@-`git ls-files`}
+if test $# -ge 1; then
+    files=$@
+else
+    files=`git ls-files`
+fi
 
 # hide cursor
 
@@ -129,4 +134,4 @@ heading
 effort $files | tee $tmp && sort_effort
 echo
 
-show_cursor
+show_cursor