Add 'when' param support to Toc tag and tests#29

goldnead wants to merge 2 commits intomaingoldnead/statamic-toc:mainfrom

28-error-antlr_027-encountered-recursive-node-without-a-parent-node-during-processinggoldnead/statamic-toc:28-error-antlr_027-encountered-recursive-node-without-a-parent-node-during-processingCopy head branch name to clipboard