Same restriction for email addresses than recently done for url. An email address is now definitively no more than 254 characters:
https://en.wikipedia.org/wiki/Email_address#Syntax
http://stackoverflow.com/questions/386294/what-is-the-maximum-length-of-a-valid-email-address#answer-574698
Also a CC number and date are respectively no more than 19 and 4 digits: https://en.wikipedia.org/wiki/ISO/IEC_7813

I decided to not limit the tel numbers (now 60 chars seems plenty enough), maybe someone will even needs to increase in a far future :)

While at it, normalises fieldtypepostnew.xml:
* Removes confusing comment in header
* Restricts most types like in fieldtypepostgres.xml (no needs to have them longer), but keep unlimited (actually 2GB max): comment, description


git-svn-id: https://svn.apache.org/repos/asf/ofbiz/trunk@1529674 13f79535-47bb-0310-9956-ffa450edef68