[RFC] Fixturetest examples - move test contents to use example scripts for contents

[RonnyPfannschmidt]

this is a initial move of various things to example scripts as well as a removal of formatting strings to test files

the main benefit of having the actual test examples in text files is that we can run them directly and debug pytest directly

it also eases adding extracted examples of breakages to the testsuite, just copy in a folder an write a minimal testcase just taking and running it

[coveralls]

Coverage increased (+0.06%) to 92.665% when pulling 0fd86ec on RonnyPfannschmidt:fixturetest-examples into 8680dfc on pytest-dev:features.

[RonnyPfannschmidt]

its a good start as is, i dont want to work on more until its merged

[nicoddemus]

Well done @RonnyPfannschmidt! (Sorry about the delay)