Adiciona tutorial Pelican

Criando sites estáticos com Pelican
arthur.4lves@gmail.com
Altera plugins modules test
Testando com pelican== 3.4
Alterado conforme warning:

WARNING: PLUGIN_PATH setting has been replaced by PLUGIN_PATHS, moving
it to the new setting name.

WARNING: Defining PLUGIN_PATHS setting as string has been deprecated
(should be a list)
retorna original gitmodules
Update requirements.txt
Merge branch 'pelican' of https://github.com/arthur-alves/pythonclub.github.io into arthur-alves-pelican
corrigido data artigo arthur e removido acento no slug do titulo
Merge branch 'arthur-alves-pelican' into pelican