Update README

[tugberkugurlu]

Update README file with:

• Instructions on how to get this up and going.
• General info about the usage.
• License info.
• Contribution guidelines (simply refer to CONTRIBUTING.md file when it's there)
• Add VB usage screenshot.

[AdamSpeight2008]

VB.net screenshot

[tugberkugurlu]

@AdamSpeight2008 awesome, thanks! I just noticed that "Check Parameter for null" needs to be "Check parameter for null", with parameter starting with lowercase. I made the change and committed.

[AdamSpeight2008]

Having reread it, in the context of VB.net is should be Nothing rather than null