ci(travis): auto release prep for 3.10.0 (optimizely#445)

ci(travis): auto release prep for 3.9.0 (optimizely#436)

ci(travis): auto release prep for 3.8.1 (optimizely#426)

ci(travis): auto release prep for 3.8.0 (optimizely#412)

ci(travis): auto release prep for 3.7.1 (optimizely#400)

Co-authored-by: optibot <optibot@users.noreply.github.com>

ci(travis): auto release prep for 3.7.0 (optimizely#392)

ci(travis): auto release prep for 3.6.1 (optimizely#379)

ci(travis): auto release prep for 3.6.0 (optimizely#375)

Co-authored-by: optibot <optibot@users.noreply.github.com>

ci(travis): auto release prep for 3.5.0 (optimizely#372)

Co-authored-by: optibot <optibot@users.noreply.github.com>

ci(travis): auto release prep for 3.4.1 (optimizely#369)

Co-authored-by: optibot <optibot@users.noreply.github.com>