README improvements

.github/CONTRIBUTING.md

@@ -1,9 +1,6 @@
 * Bug reports and feature requests are welcome in [the issues][issues]
-* For questions and discussion there's the [Slack room][slack] ([invititation here][slackinvite])
 * Pull Requests are welcome. For more complex changes and features it's
   recommended to open an issue with the feature request first
 * Documentation contributions are as important as code contributions
 
 [issues]: https://github.com/go-task/task/issues
-[slack]: https://gophers.slack.com/messages/task
-[slackinvite]: https://invite.slack.golangbridge.org/

.github/ISSUE_TEMPLATE.md

@@ -1,7 +1,4 @@
 <!--
-For questions and general talk there's the Slack room: https://gophers.slack.com/messages/task
-Invite to the Slack is available in this link: https://invite.slack.golangbridge.org/
-
 If relevant, include the following information:
 - Task version
 - OS

README.md

@@ -1,4 +1,3 @@
-[![Join Slack room](https://img.shields.io/badge/%23task-chat%20room-blue.svg)](https://gophers.slack.com/messages/task)
 [![Build Status](https://travis-ci.org/go-task/task.svg?branch=master)](https://travis-ci.org/go-task/task)
 
 # Task - A task runner / simpler Make alternative written in Go
@@ -127,7 +126,7 @@ tasks:
 
 ### OS specific task
 
-If you add a `Taskfile_{{GOOS}}.yml` you can override or amend your taskfile
+If you add a `Taskfile_{{GOOS}}.yml` you can override or amend your Taskfile
 based on the operating system.
 
 Example:
@@ -325,7 +324,6 @@ If you prefer this check to be made by the content of the files, instead of
 its timestamp, just set the `method` property to `checksum`.
 You will probably want to ignore the `.task` folder in your `.gitignore` file
 (It's there that Task stores the last checksum).
-This feature is still experimental and can change until it's stable.
 
 ```yml
 version: '2'