add publish target in makefile

Makefile

@@ -14,17 +14,24 @@ else
 	TEST_COMMAND = nosetests --with-doctest
 endif
 
+MSG ?= update documentation
 
 help:
 	@echo 'Use "make test" to run all the unit tests and docstring tests.'
 	@echo 'Use "make pep8" to validate PEP8 compliance.'
 	@echo 'Use "make html" to create html documentation with sphinx'
 	@echo 'Use "make all" to run all the targets listed above.'
+	@echo 'Use "MSG=whatever_update_msg make publish" to create html documentation and upload to github pages.'
 test:
 	$(TEST_COMMAND)
 pep8:
 	flake8 *.py
 html:
 	make -C doc clean html
+publish:
+	make -C doc clean
+	git clone -b gh-pages --single-branch git@github.com:RNAer/dumpling.git doc/_build/html
+	make -C doc html
+	cd doc/_build/html && git add * && git commit -m "$(MSG)" && git push origin gh-pages
 
 all: test pep8 html