[Java] Upgrade to Checkstyle 8.0.
[Java] Upgrade to Checkstyle 8.0.

EvilMcJerkface/Aeron,EvilMcJerkface/Aeron,galderz/Aeron,galderz/Aeron,galderz/Aeron,real-logic/Aeron,galderz/Aeron,EvilMcJerkface/Aeron,mikeb01/Aeron,real-logic/Aeron,mikeb01/Aeron,mikeb01/Aeron,mikeb01/Aeron,real-logic/Aeron,real-logic/Aeron,EvilMcJerkface/Aeron