Word insert test correction

Fixes #1
The problem was that the expectation does not expect the characters for
an escaped new line, and the new lines are already there in the test as
represented by a new line.

When we remove the \n characters, then it still fails, because the first
line is not meant to be blank.
refactor exercise 3

change if !exist? to unless exist? to improve readability
add first attempt at exercise 8"
change name of test
add attempt at exercise 9
Merge branch 'Issue_1_Failing_test' of https://bitbucket.org/jemise111/rubylearning-exercises