Prepare 0.10 release

[johanjanssens]

1. Multisite support #117

This PR implements multi-site support for pages. A default installation of pages will use the root /joomlatools-pages folder, with multi-site is enabled it becomes possible to re-configure this default folder and add additional sites.

2. Refactor redirect handling #120

This PR refactors how redirects internally work. Redirects can be configured per page, in the site configuration or in the global configuration.

Additional configuration options

• template: [string]
• template_config: [array]
• sites: [array] (only in global configuration-pages.php for multi-site setup)