[FEAT] Add prepend action

[crutchcorn]

One idea that's garnered a bit of attention in #181 is that we want to prepend a feature to the start of the file, similar to how append adds a new line to the end of the file

[mrpriyansh]

Hey @crutchcorn , I am interested in contributing to the plop. Can I take this enhancement to start on?

[crutchcorn]

@mrpriyansh go for it!

[mrpriyansh]

Hey @crutchcorn , I have raised a PR that includes the support for prepend. Please review it. This is my first oss contribution let me know if I have missed something.

#414