Small version of the grep command line tool, that searches for a given string inside a text file.
You can test it with the poem.txt file in the repo or with your own text file by running:
cargo run <search> <filename.txt>
The search is case sensitive by default. If you want to make it case insensitive you just need to set the CASE_INSENSITIVE environment variable to any value, for example:
CASE_INSENSITIVE=1