0.15.0

This change adds mpy cross compiled *.mpy files based on MicroPython 1.27.0 to the be_upy_blink directory. These files are listed in package_mpy.json and can be installed via mip like

import mip
mip.install("github:brainelectronics/micropython-package-template/package_mpy.json")

or from the command line

mpremote mip install github:brainelectronics/micropython-package-template/package_mpy.json@feature/provide-mpy-cross-files

The pre-commit hook mpy-cross is generating the latest *.mpy files of the be_upy_blink directory. If new .mpy files are created or change by this hook, the hook will raise an error.
The pre-commit hook upy-package-mpy is added to verify the package_mpy.json file list is up to date.

This closes #36