Adds local Vale usage to starter pack

[SecondSkoll]

sp-vale command installs and runs vale against $(TARGET). Default target is index.rst.

Adds obtained files to .gitignore to ensure they are not committed

[akcano]

@SecondSkoll Works for me. However, I would naturally expect vale to run against all content files in the local directory recursively; is that too much to ask?

[SecondSkoll]

I've changed the Vale command to operate on the entire directory and I scoped it to MD, RST, and TXT files.

I also had to make some small revisions to the README, as it was raising some issues.

[akcano]

EDIT: looks awesome.

[ru-fu]

Oops ... My intention was to keep the PR open for a day or so before merging to allow others to add any comments, but now there's a conflict in the readme after merging other stuff. Sorry. :grimacing: