Added the docu folder with description of stuttering mistakes.

documentation/MistakeDefinitions.txt

+Stuttering/repetition mistakes:
+
+- 2 or more times the same word in a row in the shadow, while it only appears once in the source. Example: 'en' and 'en' in file 7 (2nd 'en' is repetition)
+- incorrectly shadowed word before a correctly shadowed word is the beginning of the correctly shadowed word. Example: 'toe' and 'toestuurt' in file 7 ('toe' is repetition)
+- incorrectly shadowed word after a correctly shadowed word is the end of the correctly shadowed word. Example: 'bestaat' and 'staat' in file 9 ('staat' is repetition)
+- Same as two above, but with more than 1 word. Example 'je', 'dat', 'je' and 'dat' in file 17 (latter 'je' and 'dat' are repetitions)
\ No newline at end of file