Various bug fixes and a security fix for encrypted cookies in Laravel

UX/UI Improvements

• Added new Paragraph Formats option to the Editor Settings page, which allows you to control the available tags in the Paragraph Formats button.

API Changes

• The Encryptable trait now encrypts "empty" values correctly, such as the number zero and an empty string. The only value that is left unencrypted is a null value.
• Fixed docblocks in the October\Rain\Network\Http class that referred to the $options property as an array instead of the callable that is actually used

Bug Fixes

• Unit tests involving authentication are now namespaced to backend.auth, to prevent conflicts with other authentication libraries.
• Fixed "use statement with non-compound names has no effect" when attempting to import classes already in the root namespace (like facades) in the CMS PHP code section.
• Fixed a bug where the text entry of a taglist field would remain after the tag has been created.
• Resolved an issue where PHP max_input_vars limits would prevent "group" filters from working if they contained more options than max_input_vars would allow.
• Fixed support for ignoreTimezone in date and daterange filter scope types.
• Fixed issue with Arabic translation in the backend where Indic numerals were being used instead of Arabic numerals for the datepicker FormWidget which was confusing the serverside processing of date values.
• Fixed issue where an incorrect <textarea> tag definition broke the popup editor for stringList and text type fields in the Inspector.

Security Improvements

• Improved validation of encrypted cookies by locking cookie values to the cookie they were created for. See the security advisory for more information.

Translation Improvements

• Improved French translation.

Community Improvements

• Added note in config/cms.php for handling URL generation for uploaded files when using October in a subfolder installation.