v2.3.0

Cuba v2.3.0

Diff since v2.2.0

Closed issues:

• Combining Cuba.jl with GPU (#36)
• Controlling Size of X Matrix using nvec (#37)
• change license to MIT? (#40)

Merged pull requests:

• Test on Alpine Linux (#35) (@giordano)
• Upgrade Documenter to v0.27 (#38) (@giordano)
• add support for userdata and the corresponding tests (#39) (@kunyuan)
• [CI] Move Aarch64 to Cirrus and add FreeBSD as well (#41) (@giordano)
• [CI] Remove Drone (#42) (@giordano)
• Switch license to MIT (#43) (@giordano)