Make SchemaDumper dump primary keys not named 'id' correctly in SQLite3

Consider this schema:

create_table :pets, :primary_key => :pet_id ,:force => true do |t|
  t.string :name
  t.integer :owner_id, :integer
end

This gets incorrectly dumped like the following when using SQLite3 (:pet_id is no longer a pk):

create_table "pets", :id => false, :force => true do |t|
  t.integer "pet_id",   :null => false
  t.string  "name"
  t.integer "owner_id"
  t.integer "integer"
end

This patch fixes this so the output is correct:

create_table "pets", :primary_key => "pet_id", :force => true do |t|
  t.string  "name"
  t.integer "owner_id"
  t.integer "integer"
end

We ran into this bug when developing against a legacy database schema. We wanted the test and development environments to run against SQLite3 and production against SQL Server (yikes).

The original fix was found in the old Trac - Ticket 6095

The fix can be cherry-picked from Git in this commit