Fix links to glossary

This commit only cover the changes done by

    $ for i in $(grep -lr -e "(../gloss.html" ./novice); do sed -i 's/\.\.\/gloss\.html/\.\.\/\.\.\/gloss\.html/' $i; done
    $ for i in $(grep -lr -e "(../gloss.html" ./intermediate); do sed -i 's/\.\.\/gloss\.html/\.\.\/\.\.\/gloss\.html/' $i; done

Close #393.
Merge pull request #394 from r-gaia-cs/fix-gloss-links

Fix links to glossary