Fixed doc linking

Develop doc merge (#16)

* Added more test coverage.

* Added StyleCI

* Fixed the Style

* Refactored code and unit test.

* Remove globals.

* Minor refactor

* Minor refactor

* Minor refactor

* Updated the PHPdocs

* Changed the comment positioning

* Update .scrutinizer.yml

* Update .scrutinizer.yml

* Removed scruitnizer and StyleCI

* Added documentation

* updated the documentation

* updated the documentation

* updated the documentation

* updated the documentation

* updated the documentation

* updated the documentation

* updated the documentation

* updated the documentation

* updated the documentation

* Update Collection.md

* Update Collection.md

* Create ArrayHelper.md

* Update Collection.md

* Update index.md

* Added Encrypter documentation.

* Update composer.json

* Documentation for StringHelper

* Documentation for StringHelper

* Updated the Collection.

* Minor composer.json refactor.

* Refactored the test.

* Refactored the test and added more docs.

* Added more docs

* Added Mailgun transport and rest of the docs.

* Fixed the link.

* Fixed the link.

* Merged master.

* Merged master.

* Update README.md

* Updated README

* Updated README

* Added  random method to StringHelper and other refactor.

* Merge latest changes from Laravel to Collection and updated the docs accordingly.

* updated the docs

* Added ProcessManager and other addition/refactoring.

* Fixed PHP 5.6 error.

* Fixed the hardcoded function error.

* Added more test.

* Used mock for ProcessManager test.

* Changed signature of the ProcessManager constructor.

* Added callback test for ProcessManager.

* Added few methods to StringHelper.

* Updated the docs.

* Updated the docs.

* Updated the docs.

* Lowered PHP requirements.

* Reverted lowered PHP requirements.

* Update README.md

* Fixed doc links.

* Fixed doc links.

* Fixed doc links.