Add airstack_image_name to env directory

Works with updated bootstrap makefile.
Ignore build directory

Updated gitignore
Remove old dockerfiles templates
Update Makefile templates lists

Update development and test lists. 
Only the test build has the tests included now.
Remove hardcoded image name from makefile

Makes core consistent with nodejs image for now. Can update later once we have a clearer idea about loading vars into makefiles. e.g. using config file vs env vars vs env files.