Add support on wedocs shortcode to include or exclude by tags

[rubengc]

trafficstars

New args like include_tags and exclude_tags will be really useful to show different types of docs

For example, I want to setup and separate docs by two tags: docs and dev-docs

With this new shortcode attributes will be really easy separate them using: [wedocs include_tags="docs"] [wedocs include_tags="dev-docs"]