Task is looking for a contributor

Many times potential contributors don't know where to start, they see a long list of issues, don't know if the issue will take them 30min or 30 days to complete, might believe that the issue is already assigned, etc.

To solve this problem and help new contributors join the project I'm creating two things:

• An issue tag called: easy which will help potential contributors identify what they can work on
• A short text to copy+paste into each "contributor ready" issue description which:
• Encourages them to work on this issue
• Links them to other tasks tagged as easy
• Links them to the First steps as a contributor and Contributing 101 pages

Text

## Contributor wanted
This issue is [easy](https://github.com/andresriancho/w3af/issues?q=is%3Aopen+is%3Aissue+label%3Aeasy)
and looking for a contributor, just add a comment saying you'll do it's yours!

Not sure where to start from? Take a look at our [First steps as a contributor](https://github.com/andresriancho/w3af/wiki/First-steps-as-a-contributor) and [Contributing 101](https://github.com/andresriancho/w3af/wiki/Contributing-101) wiki pages.

Other interesting tasks which can be completed by new `w3af` contributors can be found [here](https://github.com/andresriancho/w3af/issues?q=is%3Aopen+is%3Aissue+label%3Aeasy).