Fix incompatibility to new scijava LogService

[maarzt]

Add implementations for the methods that were recently added to LogService.

A new version of scijva-log-slf4j containing this changes should be released together with scijava-common 2.66.2.

[ctrueden]

Thanks @maarzt. I am releasing scijava-common 2.67.0 now (there was new API added, so a minor version bump was necessary). Please rebase this branch to eliminate the WIP:

• git fetch && git rebase -i origin/master.
• Move the WIP to the first commit in the list and change it to e.
• Save and quit to run the rebase.
• Update the POM to have <scijava-common.version>2.67.0</scijava-common.version> in the <properties> section. Commit it, changing the message accordingly. Note that you should not hardcode the <version> of any dependency, because then the melting-pot and similar tooling can no longer override the versions used on the CLI.
• git rebase --continue

It should then be the case that all commits compile with passing tests; the check-branch.sh script will verify this.

[maarzt]

Thanks for releasing the new scijava-common version. I did the rebase as you described.
But not all commits compile:

• The first commit "POM: depend on scijava-common version 2.67.0" breaks the code. (SLF4JLogService has no implementations for new LogService methods like LogService::subLogger ...)

• The last commit "SLF4JLogService: support new LogService" fixes this.

Should I squash the two commits?

[ctrueden]

Should I squash the two commits?

Sure, that's usually what we do when code changes need to happen concurrently with a dependency version update. So squashing the first two commits together, and keeping the second commit message, sounds great. Thanks.

One small typo in the message: where -> were.

[maarzt]

I think this branch is ready to be merged

[ctrueden]

Thanks @maarzt!