When creating new book Markdown files in _includes are missing

[Letme]

There are following files missing when you create a new book (probably because they are not meant to be re-created with books), but the irony is that they should be created according to quick glance over the code:

_includes: bibliography.md
_includes: bio.md
_includes: license.md
_includes: magnet_tah.md

My idea is that something goes wrong: https://github.com/chrisanthropic/Open-Publisher/blob/master/Rakefile#L58-L62 , but my rake knowledge is not close enough to decypher.

Above diff was achieved with:

# Create create folder with book title Example
docker run --rm -v $PWD/create:/Open-Publisher/Source -v $PWD/output:/Open-Publisher/Books -it ctarwater/open-publisher rake create
# Create skel folder with Example
docker run --rm -v $PWD/skel:/Open-Publisher/Source -v $PWD/output:/Open-Publisher/Books -it ctarwater/open-publisher rake skel

# Compare both structures (other files mostly whitespaces are differences)
diff --brief --recursive create/ skel/
Only in skel/: images
Only in skel/_includes: bibliography.md
Only in skel/_includes: bio.md
Files create/_includes/Example/amazon.md and skel/_includes/Example/amazon.md differ
Files create/_includes/Example/amazon_review.md and skel/_includes/Example/amazon_review.md differ
Files create/_includes/Example/chapters.md and skel/_includes/Example/chapters.md differ
Only in skel/_includes: license.md
Only in skel/_includes: magnet_tah.md
Files create/_layouts/Example/amazon.md and skel/_layouts/Example/amazon.md differ

I would be hoping its an easy fix as a workaround I will just copy the missing files from the example.