should cope with double-braced blocks now (treating them the same as
single-braced. templateEmail now returns an error, which should not be
seen as catastrophic, but reports likely mistakes.
at this point I really should've just used text/template, but I guess
this way compatibility is kept with existing custom emails. If statement
works as so:
{if variable}variable was true{endif}
{if !variable}variable was false{endif}
no else yet, just do as above (two if statements).
