convert-ome command doesn't report when complete

[petebankhead]

Bug report

Describe the bug
When converting an image from the command line, progress may be logged - but no message is given when the conversion is complete.

This is often ok when running from a terminal, but is awkward if running in eclipse - where it is less clear that the process is complete.

To Reproduce
Run a command such as

QuPath convert-ome /path/to/CMU-1-Small-Region.svs /path/to/CMU-1-Small-Region2.ome.tif 

Based only on what is printed, it looks like conversion hangs at 97% - when in fact it did terminate properly.

07:48:16.170 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Writing resolution 1 of 1 (downsample=1.0, 30 tiles)
07:48:16.173 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Writing plane 1/1
07:48:16.394 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 10% tiles
07:48:16.492 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 20% tiles
07:48:16.597 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 30% tiles
07:48:16.660 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 40% tiles
07:48:16.744 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 50% tiles
07:48:16.800 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 60% tiles
07:48:16.864 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 70% tiles
07:48:16.935 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 80% tiles
07:48:17.036 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 90% tiles
07:48:17.091 [main] [INFO ] q.l.i.writers.ome.OMEPyramidWriter - Written 97% tiles

Expected behavior
A clear message printed when conversion is successful, ideally also with timing information.

Desktop (please complete the following information):

• OS: All
• QuPath Version 0.3.0