minor testscripts improvement

[umlaeute]

• use the same interface for all test wrappers (tests/*.sh): <scriptname> <testfile-without-extension> [<mysofa2json>]

• improve argument check, and print usage information if the test-scripts are called with the wrong args

• consistent indentation and removed trailing whitespace

• pass the path to mysofa2json to the tests/nocrash.sh script as well (like for the other wrappers)

• Related: v1.3.4 test suite fails #243

[umlaeute]

some more ideas for improving the test-scripts:

• should usage errors always return 128? (currently, if my new argument checks fail, it will simply return 1)
• should we use named options for passing the mysofa2json path? e.g.

  -tests/compare.sh tests/MIT_KEMAR_large_pinna path/to/mysofa2json
  +tests/compare.sh -m path/to/mysofa2json tests/MIT_KEMAR_large_pinna

  this appears to be more extendible (what if we ever want to pass more arguments)

i can implement both if you want me to.