Improve the automatic finishing of FreeMarker constructs

Currently, when I type <# or <@, the editor automatically adds the closing >. It should also close </#, </@, ${, and #{ and <#--. Furthermore the way it auto-closes what it does is technically awkward, as it only inserts the > after the inserted # was shown and the resulting syntax highlighting was done, instead of inserting both characters in a single step.