Fix calculate_relative_path

When outdir == "." calculate_relative_path was counting that dot as a
directory and adding an extra ".." to the result. So only count parts
that don't equal ".".

Refs #2921

[SVN r52237]

tools/quickbook

@@ -1 +1 @@
-Subproject commit d86a2fe747b1abede49e669393428ef8ed46ce3d
+Subproject commit 566b8dd3698bf63567dcdaaaf8c60b78d07ffe7b