[PATCH] Sqlite adapter's copy_table should not set :id => true if :id is not a primary key

Sqlite adapter's copy_table should not set :id => true if :id is not a primary key.

We had a legacy table with a string id. Changing the table was not a good option, according to people more important than me. To recreate the table locally for development, I used a migration like the one below.

create_table :table_name, :id => false do |t|
  t.column :id,                   :string,  :limit => 40, :null => false
  t.column :value,                :integer
end


#later we tried to call

remove_column :table_name, :value

And upon calling remove_column, the whole thing blew up. When SQLiteAdapter tried to call copy_table, it set :id => true and wrote over the original id column.

The following commit will set :id => false if there is an :id column, but it's not a primary_key.