Remove gem check in sqlite adapter
Remove gem check in sqlite adapter

Sequel no longer uses the type_translation method, and I think it
will be removed in a future version.  Also, the sqlite3-ruby gem
got renamed to sqlite3.  This code was originally written to
provide a better error message for people who used the sqlite3
gem before sqlite3-ruby got renamed, but I don't think it serves
a purpose any more.

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