update: create notes from templates

[Rooyca]

Fixes

Checklist

• [x] I have made a change to this repository, be it functionality, testing, documentation, spelling, or grammar.
• [x] I updated my branch with the master branch.
• [x] I have added the necessary testing to prove my fix is effective/my feature works (or I did not modify functionality).
• [x] I have added necessary documentation about the functionality in an appropriate .md file.
• [ ] I have appropriately commented any code I have modified

Short description of what this PR does:

• I added a -t flag to the new command to create notes from a template (which by default are located in $NOTES_DIRECTORY/templates)

[Rooyca]

Thanks for all your comments. I think I edited everything you recommended, if I missed anything please let me know. Have a great day.

[Rooyca]

Aesthetically it's not the best code, but I think it should be working now... at least the tests didn't fail.

Have a great day.

[pimterry]

Merged with a last couple of small tweaks - thanks @Rooyca! I'll update the latest release to this in just a minute.

[Rooyca]

Thanks to you for your advice and patience.