[Code Style]Clean up libraries/joomla. Fixes #4554. Fixes #4552. Fixes #4543. Fixes #4532. Fixes #4538

[Code Style]Clean up libraries/joomla/linkedin

[Code Style]Clean up libraries/joomla/github

[Code Style]Clean up libraries/joomla/database

[Code Style]Clean up libraries/joomla/feed
[Code Style]Clean up libraries/joomla (oauth & mediawiki). Fixes #4556. Fixes #4557

[Code Style]Clean up libraries/joomla/oauth2
[Code Style]Clean up libraries/joomla. Fixes #4587. Fixes #4586. Fixes #4585. Fixes #4583. Fixes #4581. Fixes #4572. Fixes #4568

[Code Style]Clean up libraries/joomla/updater

[Code Style]Clean up libraries/joomla/twitter

[Code Style]Clean up libraries/joomla/table

[Code Style]Clean up libraries/joomla/string

[Code Style]Clean up libraries/joomla/filter

[Code Style]Clean up libraries/joomla/image
[Code Style]Clean up libraries/cms. Fixes #4593. Fixes #4596. Fixes #4598. Fixes #4599. Fixes #4602. Fixes #4604
Merge branch 'staging' of https://github.com/joomla/joomla-cms into staging