Merge pull request #76 from wush978/master

remove git submodule inst/ETL/slides
Merge pull request #77 from wush978/master

update version
Merge pull request #78 from wush978/master

debug typo of get_uri
Merge pull request #1 from TaiwanRUserGroup/master

pull
Add function helper Documents
Merge pull request #79 from JohnsonHsieh/master

Add helper doc
update slides
update version