feature sync slide and webapp within py3

Signed-off-by: Ace Han <ace.han@cargosmart.com>
Merge branch 'master' of https://github.com/ace-han/gotcha into py3
folder_structure_refactor according to django best practice
e.g:
project_root
    |
    |- project_itself
    |- module 1
    |- module 2
    |- ...
    |- module N
Merge branch 'master' into py3