Add case insensitive search when user adds \c to search

Adds case insensitive search by adding the ```i``` flag to the regex. Adds this when the user puts ```\c``` in their search term.
Fixes #330
The mentioned bug says ```/c```, but it's supposed to be ```\c```

It looks like this can start with `\n`, just like the below ones, which would offer an opportunity to wrap them all in a `describe` and do this setup work in a `beforeEach`.