Add info on internationalization to validation_helpers RDoc
Add info on internationalization to validation_helpers RDoc

Most of this code comes from mmontossi on IRC, thanks to him
for sharing.

uhoh-itsmaciek/sequel,freshpay/sequel,nju520/sequel,seeARMS/sequel,dennis-d/custom_sequel,davidbegin/sequel,seeARMS/sequel,Marketcircle/sequel,offshore-safety/sequel,gferguson-gd/sequel,nicohvi/sequel,nicohvi/sequel,nju520/sequel,mpalmer/sequel,yazshel/sequel,uhoh-itsmaciek/sequel,mpalmer/sequel,gferguson-gd/sequel,t-morgan/sequel,knut2/sequel,offshore-safety/sequel,chef/sequel,knut2/sequel,freshpay/sequel,yazshel/sequel,beni55/sequel,offshore-safety/sequel,reubano/sequel,beni55/sequel,reubano/sequel,bigfix/sequel,davidbegin/sequel,pfarrell/sequel,dennis-d/custom_sequel,t-morgan/sequel,pfarrell/sequel