[pxt-cli] bump version to v0.15.77 (#410)

[pxt-cli] bump version to v0.15.76 (#407)

[pxt-cli] bump version to v0.15.75 (#406)

[pxt-cli] bump version to v0.15.74 (#403)

[pxt-cli] bump version to v0.15.73 (#401)

[pxt-cli] bump version to v0.15.72 (#398)

[pxt-cli] bump version to v0.15.71 (#396)

[pxt-cli] bump version to v0.15.70 (#391)

[pxt-cli] bump version to v0.15.69 (#389)

[pxt-cli] bump version to v0.15.68 (#388)