Python API: Add Makefile target to generate api docs.

We currently generate the epydocs from the publishing script, which
means someone just looking at the repo doesn't know what command line
to use. Let's add a Makefile rule to do the work.

This work is based on: #15

(cherry picked from commit 6b402f8)

Author: Philip Langdale

python/.gitignore

@@ -1,5 +1,6 @@
 build/
 dist/
+doc/
 *.egg-info/
 .git-hash
 

python/Makefile

@@ -14,10 +14,15 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+DOCDIR ?= doc
+
 .PHONY: help
 help:
 	@echo 'The build targets are:'
 	@echo '  dist		: Create a source distribution tarball'
+	@echo '  test		: Run unit tests'
+	@echo '  doc		: Generate epydoc format documentation'
+	@echo '  clean		: Clean up all generated files'
 
 .PHONY: test
 test:
@@ -33,5 +38,10 @@ dist: test
 clean:
 	rm -rf *.egg-info
 	rm -rf dist
+	rm -rf doc
 	rm -rf build
 	find . -name *.py[co] -exec rm -f {} \;
+
+.PHONY: doc
+doc:
+	epydoc -v --html  -o $(DOCDIR) -n python-cm_api `find src -name "*.py"`