Use Flux flows to read input and output data of Metamorph testcases

[cboehme]

The input and output of Metamorph xml testcases can be specified in a number of formats. However, the current implementation requires a special Reader class for each data format. Using Flux this requirement could be removed. The idea is to have a property file which specifies for each supported mime-type a Flux flow for reading this format. The flow would differ from standard flows in that their first element must implement XmlReceiver and the last send its data to a StreamReceiver. Textual data could be read by using an xml-handler that only accepts character data and discards all elements. The properties file could look as followed:

application/pica-x = handle-text-only | as-lines | decode-pica
text/cgentity+xml = handle-cgxml

In order to handle input and output included in external files. A second properties file could be used in which the flows expect an ObjectReceiver for Java IO-Reader as first element.