Matchit: multiline tags and `else` statement

[buzuck]

Hi 🙂

When a tag is stretches on multiple lines for readability, it is no longer detected by the plugin matchit/match-up

{% for very_long in dict
   if true and not false %}
[...]
{% endfor %}

I tried to change the variable b:match_words by adding a \_ with no luck though:
'{%[-+]\? *\%(end\)\@!\(\w\+\)\>\_.\{-}%}:{%-\? *end\1\>.\{-}%}'

There is also some improvement that could be done on this plugin. The else statement is not paired with if/endif.