Better modularization of makefiles

Help descriptions are in their own files.

Makefile

 SHELL := /bin/bash
 .PHONY: help requirements clean build test pkg
 
-include *.mk
+help: main.help
 
-help:
+main.help:
 	@echo ''
 	@echo 'Makefile for the edX Configuration'
 	@echo ''
@@ -14,30 +14,9 @@ help:
 	@echo '    make pkg                       package everything'
 	@echo '    make clean                     remove build by-products'
 	@echo ''
-	@echo '    Docker:'
-	@echo '        $$image: any dockerhub image'
-	@echo '        $$container: any container defined in docker/build/$$container/Dockerfile'
-	@echo ''
-	@echo '        make $(docker_pull)$$image        pull $$image from dockerhub'
-	@echo ''
-	@echo '        make $(docker_build)$$container   build $$container'
-	@echo '        make $(docker_test)$$container    test that $$container will build'
-	@echo '        make $(docker_pkg)$$container     package $$container for a push to dockerhub'
-	@echo '        make $(docker_push)$$container    push $$container to dockerhub '
-	@echo ''
-	@echo '        make docker.build          build all defined docker containers (based on dockerhub base images)'
-	@echo '        make docker.test           test all defined docker containers'
-	@echo '        make docker.pkg            package all defined docker containers (using local base images)'
-	@echo '        make docker.push           push all defined docker containers'
-	@echo ''
-	@echo '    Tests:'
-	@echo '        test.syntax                Run all syntax tests'
-	@echo '        test.syntax.json           Run syntax tests on .json files'
-	@echo '        test.syntax.yml            Run syntax tests on .yml files'
-	@echo '        test.syntax.jinja          Run syntax tests on .j2 files'
-	@echo '        test.edx_east_roles        Run validation on edx-east roles'
-	@echo ''
 
 requirements:
 	pip install -qr pre-requirements.txt --exists-action w
 	pip install -qr requirements.txt --exists-action w
+
+include *.mk

docker.mk

@@ -14,6 +14,26 @@ docker_test=docker.test.
 docker_pkg=docker.pkg.
 docker_push=docker.push.
 
+help: docker.help
+
+docker.help:
+	@echo '    Docker:'
+	@echo '        $$image: any dockerhub image'
+	@echo '        $$container: any container defined in docker/build/$$container/Dockerfile'
+	@echo ''
+	@echo '        $(docker_pull)$$image        pull $$image from dockerhub'
+	@echo ''
+	@echo '        $(docker_build)$$container   build $$container'
+	@echo '        $(docker_test)$$container    test that $$container will build'
+	@echo '        $(docker_pkg)$$container     package $$container for a push to dockerhub'
+	@echo '        $(docker_push)$$container    push $$container to dockerhub '
+	@echo ''
+	@echo '        docker.build          build all defined docker containers (based on dockerhub base images)'
+	@echo '        docker.test           test all defined docker containers'
+	@echo '        docker.pkg            package all defined docker containers (using local base images)'
+	@echo '        docker.push           push all defined docker containers'
+	@echo ''
+
 # N.B. / is used as a separator so that % will match the /
 # in something like 'edxops/trusty-common:latest'
 # Also, make can't handle ':' in filenames, so we instead '@'
@@ -70,12 +90,12 @@ $(docker_push)%: $(docker_pkg)%
 
 .build/%/Dockerfile.test: docker/build/%/Dockerfile Makefile
 	@mkdir -p .build/$*
-# perl p (print the line) n (loop over every line) e (exec the regex), like sed but cross platform
+	@# perl p (print the line) n (loop over every line) e (exec the regex), like sed but cross platform
 	@perl -pne "s#FROM edxops/([^:]+)(:\S*)?#FROM \1:test#" $< > $@
 
 .build/%/Dockerfile.pkg: docker/build/%/Dockerfile Makefile
 	@mkdir -p .build/$*
-# perl p (print the line) n (loop over every line) e (exec the regex), like sed but cross platform
+	@# perl p (print the line) n (loop over every line) e (exec the regex), like sed but cross platform
 	@perl -pne "s#FROM edxops/([^:]+)(:\S*)?#FROM \1:test#" $< > $@
 
 -include $(foreach image,$(images),.build/$(image)/Dockerfile.d)

test.mk

-
 yml_files:=$(shell find . -name "*.yml")
 json_files:=$(shell find . -name "*.json")
 # $(images) is calculated in the docker.mk file
 
+help: test.help
+
+test.help:
+	@echo '    Tests:'
+	@echo '        test.syntax                Run all syntax tests'
+	@echo '        test.syntax.json           Run syntax tests on .json files'
+	@echo '        test.syntax.yml            Run syntax tests on .yml files'
+	@echo '        test.syntax.jinja          Run syntax tests on .j2 files'
+	@echo '        test.edx_east_roles        Run validation on edx-east roles'
+	@echo ''
+
 test: test.syntax test.edx_east_roles
 
 test.syntax: test.syntax.yml test.syntax.json test.syntax.dockerfiles
@@ -19,7 +29,7 @@ test.syntax.json/%:
 
 test.syntax.dockerfiles:
 	python util/check_dockerfile_coverage.py "$(images)"
-	
+
 test.edx_east_roles:
 	tests/test_edx_east_roles.sh