Fixes a bug whereby `0` is interpreted as falsy

• Fixes a bug whereby an input of 0 wouldn't clear the buffer and
  wouldn't reset the readIntent status leading to pipelines
  potentially becoming completely blocked on reading
• Changes a false to null in QueueBuffer
• Adds all the new PHP 7 versions to the Travis build
• Ignores the .vscode folder
• Corrects build script (how was this working before???)
• Adds a test to show the above behaviour is fixed

More Scheduler Control

Merge pull request #16 from ElvenSpellmaker/feature/run-x-times

Implements the ability to run `x` times.

PipeSys Examples And Various Bugfixes

• Adds various examples of PipeSys behaviour. Implements #12.
• Adds the examples to Travis as tests.
• Corrects a couple of bugs: #9 and #10.

PipeSys Version 2 Refactor

• Adds phpcs and phpmd and a Travis file for checking the outcome.
• Commands now handle all their own logic leaving less for the Scheduler.
• Implements StdErr channels (Closes #5).
• Commands may now have an unlimited number of channels which can be input or
  output channels or both.
• Bumps the version to PHP 5.6 minimum.
• Updates the README.

PipeSys Initial Release

1.0.0

PipeSys Initial Release