Documented migration steps for version 1.1
Documented migration steps for version 1.1

Covers the following:

- Usage of the `OriginalMessages` middleware.
- How to create and use programmatic pipelines.
- How to use the new error handling capabilities present in Stratigility 1.3+.

It also includes a full example incorporating all these changes.

ezimuel/zend-expressive,zf2timo/zend-expressive,acelaya/zend-expressive,moderndeveloperllc/zend-expressive