Review updated solutions

[sumedh10]

In Ch5 branch:

https://github.com/datacamp/courses-intro-to-unix-shell/tree/ch05-2018-05

https://www.datacamp.com/teach/repositories/1395/branches/ch05-2018-05

I updated solutions to 2 sub-exercises which had extra code (redundant, as far as I can tell). The exercises work fine and the build passes. Still it would be good if you can review the commits before I merge it into master

• does 5-5 still work? (this should close #133 )
• does 5-7 still work?

[gvwilson]

Thanks - the exercise keeps the previous state of the shell, so if the user did the right thing, we can chain like this. (I was copying in a solution file because I wasn't sure they would do the right thing each time.)