Convert remaining repositories to GitHub Actions

[ctrueden]

Here's a list of artifacts still using Travis, according to status.scijava.org:

Infrastructure

• [x] sc.fiji : fiji-builds [ @ctrueden ]

First party

• [ ] net.imagej : imagej-launcher
• [ ] net.imagej : tutorials (converted but failing)

Python

• [x] net.imagej : pyimagej
• [x] net.imglib2 : imglyb [ @hinerm ]
• [x] org.scijava : jgo [ @hinerm ]
• [x] org.scijava : scyjava [ @hinerm ]

Third party

• [x] flimlib : flimj-ops
• [x] flimlib : flimj-ui
• [x] mpicbg : mpicbg + mpicbg_
• [x] sc.fiji : z_spacing
• [x] graphics.scenery : scenery
• [ ] sc.iview : sciview

Javadoc

• [x] flimlib : flimlib-javadoc [ @ctrueden ]
• [x] graphics.scenery : sciview-javadoc [ @ctrueden ]
• [x] io.scif : scifio-javadoc [ @ctrueden ]
• [x] loci : loci-javadoc [ @ctrueden ]
• [x] net.imagej : imagej-javadoc [ @ctrueden ]
• [x] net.imglib2 : imglib2-javadoc [ @ctrueden ]
• [x] org.bonej : bonej-javadoc [ @ctrueden ]
• [x] org.scijava : java3d-javadoc [ @ctrueden ]
• [x] org.scijava : javadoc.scijava.org [ @ctrueden ]
• [x] org.scijava : scijava-javadoc [ @ctrueden ]
• [x] sc.fiji : fiji-javadoc [ @ctrueden ]

[ctrueden]

I did another pass through projects still using Travis CI:

• I converted uw-loci and flimlib projects.
• I filed PRs for the N5 projects.
• The javadoc projects are no longer an issue because I am redoing how javadoc is done and those repositories no longer exist; see #130.
• About sciview: I think it has already moved over to GitHub Actions, but still has the Travis CI stuff hanging around as well.
• The fiji-builds logic is converted to GitHub Actions, just disabled for now because I'm too dumb to understand how caching works (fiji/fiji-builds#7).

That just leaves imagej/imagej-launcher and imagej/tutorials.