Setup travis integration for automatic linting and potential other QA processes

[TimDaub]

Scope

• Currently the code base of Planet A is only linted locally
• When a contributor is creating a PR, code format is hence not considered an acceptance critera

Deliverables

• Like on the upstream repo (leapdao/plasma-burner-wallet), use a service like travis-ci that lints the in the PR committed code

Gains for the project

• Better code quality and not fighting about formatting

Roles

bounty gardener: @TimDaub / 10%
bounty worker: name / 75%
bounty reviewer: name / 15%