v18.8.1

Feature

• Add CONTRIBUTING.md by @dennisklein @ChristianTackeGSI in d1c872c, 93dfc56
• Rename *LinkDef.h to LinkDef.h by @ChristianTackeGSI in 0cba033,
• Fix the FairRoot targets by @fuhlig1 in a269598
• Allow running FairRun without sink by @karabowi in e0807d9

Bugfix

• Fix Ex1Processor by @ChristianTackeGSI in edb7657 (issue #1286)

Clean-up

• FairEventHeader by @ChristianTackeGSI in cb62974
• FairRun by @ChristianTackeGSI in 3aae2bc
• parbase by @ChristianTackeGSI in 393178b, 65b6434, ec643c9
• FairRunSim by @ChristianTackeGSI in b68c701, cd604e6, 925099e
• Serialization example by @rbx in ff43868, 676d34b, 2180b56, b33bc04, aee515b

Full Changelog: v18.8.0...v18.8.1