Merge branch 'version-0.6.5-release' into 'master'

Version 0.6.5 release

See merge request lscsoft/bilby!729

Version 0.6.4 release

Merge branch '0.6.3_release' into 'master'

Version 0.6.3 release

See merge request lscsoft/bilby!691

Merge branch '0.6.2_release' into 'master'

0.6.2 release

See merge request lscsoft/bilby!685

Version 0.6.1 release

Merge branch '0.6.0-release' into 'master'

Version 0.6.0 release

See merge request lscsoft/bilby!664

Merge branch 'version-0.5.9-release' into 'master'

Version 0.5.9 release

See merge request lscsoft/bilby!631

Version 0.5.8 release

Merge branch '0.5.7-release'

Version 0.5.6 release