Feature: slack and Twitter

The documentation is updated to show how and why we use
Twitter and Slack. Integrations are mentioned and linked, too.

- fixes: #7
- fixes: #2
- addresses: #8
- addresses: #1
- addresses: #6

docs/SLACK.md

@@ -1,7 +1,44 @@
 # Slack
 
-- reasons for slack
-- provided functionality
-- how to use (web, apps)
-- channels
-- integrations
+[Slack](https://whiletruedoio.slack.com) is free chat solution, that is used by
+many development teams and provides very nice integrations in different tools.
+Even if it is not Open Source, it provides much benefits and is very common.
+
+We are using Slack as the internal development chat to get notifications and
+discuss development topics.
+
+## Reasons
+
+- desktop, mobile and web client
+- widely used
+- many integrations
+- works well with GitHub
+
+## Docs & Links
+
+- Site: <https://slack.com>
+- Docs: <https://slack.com/help>
+- Apps: <https://slack.com/apps>
+
+## Features
+
+- extendable via Apps and webhooks
+- supports markdown and code highlighting
+- group chats and channels
+- one-to-one voice calls (group calls only in premium)
+- public and private channels
+
+## Usage
+
+What could you say about a chat. It is a chat and can be used like one. Write
+stuff down, inform people and check notifications. Please be aware, that a
+chat like slack should not be used for very important messages, but short living
+information or notifications. People may or may not check the messages
+
+## Integrations
+
+Currently we integrate Slack with other software.
+
+- GitHub: <https://slack.github.com/>
+- Twitter: <https://slack.com/help/articles/205346227-Twitter-for-Slack>
+- Uptimerobot: <https://uptimerobot.com/integrations/>

docs/TWITTER.md

@@ -1,5 +1,25 @@
+# Twitter
 
-- reasons for twitter
-- provided functionality
-- how to use (web, apps)
-- integrations
+[Twitter](https://twitter.com/whiletruedoio) is a social network, mostly for
+short news and messages. It is very well suited to keep in touch with the tech
+community and providing updates for releases, blogs and more.
+
+## Reasons
+
+- many tech people there
+- short message format
+- GitHub provides a twitter handle option
+
+## Features
+
+- typical social media stuff
+- short messages (160 chars)
+- images, urls and attachments supported
+
+## Integrations
+
+- GitHub organization shows Twitter handle
+- Github profile shows Twitter handle
+- new Tweets from [@whiletruedoio](https://twitter.com/whiletruedoio) are shown
+  in [Slack](SLACK.md)
+- [Zapier](ZAPIER.md) is used to publish news via Twitter