Base structure for addUnits/addMachines in ecs

Checkpoint.

Add units and machines added to ECS - tests pass.

Make lint happy

Tests added for new ECS methods.
Merge pull request #304 from makyo/more-ecs-calls

Add units and machines added to ECS - tests pass.
Tests added for new ECS methods.

To QA - from the console, follow the steps here: https://gist.github.com/makyo/9dc0503658b439d1ed7e