fix #273

[alexiscreuzot]

Summary

Here's an implementation of a possible improvement linked to issue #273. Please do review it carefully as Ruby isn't my strong suit.

Feature

You can now optionally specify an array of suffixes that need to be processed by liftoff as resource (ie not be added to the Compile Sources phase), using the key additional_resource_suffixes.

Example

additional_resource_suffixes:
 - txt
 - yaml
 - ttf

Test

See https://github.com/kirualex/liftoff/blob/feature/%23273/spec/project_configuration_spec.rb#L76-L84