id independent export

records referencing other tables are filled in with values found in
these tables - id is not part of the seeds.rb but is obtained using
find_by() functions
models are ordered in output file in a way first models not referencing
other models are exported, then models referencing already exported ones
- it can be used to seed empty database without worrying if ids match
cosmetic change
merge of github and local branch, made by mistake

Conflicts:
	lib/seed_dump/dump_methods.rb
	lib/seed_dump/environment.rb