Added the ability to define custom settings and mappings in a config

[TylerLeonhardt]

defmodule MyApp.SomeModel do
  use ElasticSync.Schema,
    index: "some_model",
    type: "blah",
    config: {MyApp.SomeModel, :index_config}

  def index_config do
    %{settings: %{}, mappings: %{}}
  end
end

you can now define settings and mappings in a function that will get plumbed down to the creation of the elastic search index

As talked about in #5

[coveralls]

Coverage increased (+0.9%) to 80.531% when pulling 54f2a05 on tylerl0706:master into 1f6fc66 on promptworks:master.

[rzane]

is the Tirexs.get_uri_env necessary?

[rzane]

we should be consistent with the type we're expecting for config. Is it a keyword list or a map? Technically tirexs will accept both, but I'd actually prefer we consistently default to a map.

[rzane]

config should be the second arg. the function should be the last.

i don't think we need to provide a default here. especially since I plan to make all of these functions take a struct later anyway.

[rzane]

Since it isn't a required option, and since developers will just be entering raw values (not some computed value), I don't think we need to check for nil.

[rzane]

This looks great. I just have a few minor suggestions. Then, once CI is passing, this should be good to go!

[coveralls]

Coverage increased (+2.4%) to 81.982% when pulling ef21a29 on tylerl0706:master into 1f6fc66 on promptworks:master.

[coveralls]

Coverage increased (+0.6%) to 80.18% when pulling d978c05 on tylerl0706:master into 1f6fc66 on promptworks:master.

[coveralls]

Coverage increased (+0.6%) to 80.18% when pulling 8b69cdb on tylerl0706:master into 1f6fc66 on promptworks:master.

[coveralls]

Coverage increased (+0.6%) to 80.18% when pulling 8f1a25b on tylerl0706:master into 1f6fc66 on promptworks:master.

[coveralls]

Coverage increased (+0.6%) to 80.18% when pulling 7a5b7f4 on tylerl0706:master into 1f6fc66 on promptworks:master.

[rzane]

I'm good with this as soon as CI passes 👍

[coveralls]

Coverage increased (+0.4%) to 80.0% when pulling d99fbd2 on tylerl0706:master into 1f6fc66 on promptworks:master.

[coveralls]

Coverage decreased (-0.9%) to 78.761% when pulling 561681d on tylerl0706:master into 1f6fc66 on promptworks:master.

[coveralls]

Coverage increased (+0.9%) to 80.531% when pulling 0da3f89 on tylerl0706:master into 1f6fc66 on promptworks:master.

[TylerLeonhardt]

At last!