Fix TeX escaping of [].

`\\ [...] blah` was crashing LaTeX in [[The Minister and the Massacres]]
because the [ was being parsed as the optional argument to the `\\` command.

While we're at it, properly quote " and fix a missing g flag on the
smart single quote rule.

Change-Id: Ifb1ee7f16285ccca6963a66068f2a7df72922520