v0.4.0

SEAL v0.4.0

Diff since v0.3.0

Merged pull requests:

• Rename master to main (#10) (@sloede)
• Switch to GitHub actions (#11) (@sloede)
• Fix tests (#13) (@sloede)
• Try to fix failing CI test on macOS (#14) (@sloede)
• CompatHelper: bump compat for "Documenter" to "0.26" for package docs (#16) (@github-actions[bot])
• Re-enable finisher for Coveralls (#17) (@sloede)