Add alignments track option to 'Hide small indels (less than 10bp)'

[cmdcolin]

This is something that occurs during long read sequencing a lot

It's hard to find the right balance of what the best behavior is for this setting is as "hifi" reads don't suffer a lot of indels, so it might not make sense to automatically toggle it on, but

for CLR/nanopore where there are a lot of indels, the track can look like this zoomed out

but with hide indels turned on, cleans it up a bit...

other options include using subpixel rendering so it automatically toggles off at zoomed out scales, this is possible by manually editing the renderer config (minSubfeatureWidth) which could also be exposed via track menu potentially

another option is the 'quick consensus mode' (#4292) but that's a bit trickier. kinda involves calculating snpcoverage type settings, and uses that to inform pileup rendering