read in data file

[matcatc]

Instead of using an executable or script for the test data to display, allow users to provide a data file with all of the data.

Benefits:

• can read files after the fact
• custom commands If the user has a custom command/program/whatever that produces output which can be parsed, but isn't yet supported, then he/she can simply pipe the output.

Use a switch (maybe -f) to indicate that a file is being passed in instead of a runner.

 Example: TestParser_main.py -f Boost BoostFile.xml

Don't forget to allow for - and stdin.

[matcatc]

• Read in from stdin [DONE]
• Try to refactor FileRunner [DONE]
• Write tests.

[matcatc]

Just need a test for stdin. But I don't know how to implement. Seeing as its just one line that won't be covered, we can move on and come back later.