Feature tests included, code style checked, now send returns a response

Merge pull request #8 from gahlawat/development

travis updated to use composer cache

Refactor

2.1.1

refactor

Channel support added

Channels and private messaging to any user is now possible.
Code is refactored with unit testing added.

Laravel 5.5 compatibility

Package auto discovery

PSR-2

All code is reformatted following strict psr-2 coding standards.

Namespace usage shown

use Slack;

Fixed default parameters

Default fixed via constructor as default php function expects scalar values only.

First stable release

Whoa!

My first package going live!

YahooooO!