Allow PHP 8 support in composer (#50)

* Allow PHP 8 support in composer

Helps avoid this issue with the composer when running on PHP 8 environments. Pulled the commit off the suggestions from this issue #48

* Run the test suite against PHP 8

Update composer.json (#47)

Allow for Laravel 8.x Application Usage.

Use "as=fetch" in case no extension is matched (#46)

update dependencies for Laravel 7 (#42)

Update composer.json

Improved URL detection for protocol-relative URLs (#39)

Fixed #38

Update composer.json

Adds a requirements section to the README (#35)

Config file for : Size limit, exceptions, base path (#28)

* #25 deduplicate header links

* - Add config file
- Add size limit
- Add base path configuration
- Add exceptions filters
- Update test
- Updates doc

solves #23, #27

* update travis :
- remove PHP5.6,
- add PHP7.2 and 7.3

#25 deduplicate header links (#26)