support unicode punctuation better

[kmike]

Currently only a small set of chars are in punctuation regex: ,:;.!?"\). I wonder if we should add more, e.g. unicode quotes.

An example (though I'm not sure if it will be fixed by such change):

Detecting entities on their own is not always enough; in many cases what is wanted is to find the relationship between them. For example, “ street_name/STREET city_name/CITY zipcode_number/ZIPCODE form an address”, or “ phone/TEL is a phone of person/PER ”.