Fixed getIssues snippet for multiple usage

Fixes Issue #7 (check if function already exists)

Signed-off-by: Martin Gartner <martin.gartner@bitego.com>
Added basic Usage / HowTo in README.md

Signed-off-by: Martin Gartner <martin.gartner@bitego.com>
Merge pull request #8 from gadgetto/develop

Fixed getIssues snippet for multiple usage + added basic usage