Merge pull request adafruit#323 from adafruit/revert-bossac-to-1.8

revert bossac tool from 1.9 back to 1.8

Merge pull request adafruit#321 from caternuson/iss320_dotstar

Add defines for internal DotStar pins

migrate all m0 upload tool to bossac 1.8 (adafruit#318)

increase version 1.7.6 for release

bump up version for release 1.7.5

increase version for 1.7.4 release

Merge pull request adafruit#301 from adafruit/more-ci-work

More ci work

Merge pull request adafruit#300 from adafruit/fix-warnings

Fix warnings

increase version to 1.7.0 for release

increase version for release 1.6.8