Postqf

In addition to filtering JSON input and producing JSON output in the process, PostQF can now also generate a number of simple reports to answer some frequently asked questions about message queue content. The following data can be shown in reports:

* Delay reason
* Recipient address
* Recipient domain
* Sender address
* Sender domain

This release focuses on internal changes. It does not contain any new features.

* Output is now correctly rendered as _JSON_ instead of a Python _dict_.
* Simplified installation process. In addition to _pip_ based setup, an installation BASH script is now provided.

- Release 0.2 introduces the ability to use both `-a` and `-b` time filters simultaneously, in order to specify time intervals.
- Time filter strings can now use [ISO 8601](https://en.wikipedia.org/wiki/ISO_8601) strings and [Unix time](https://en.wikipedia.org/wiki/Unix_time) in addition to relative time differences expressed in the form _42m_ or _2d_. This allows users to also specify absolute points in time as arrival thresholds.

This is the first public PostQF release.