tool: show LSM viewer URL in db lsm command

[RaduBerinde]

We now show the LSM viewer URL as well in the pebble db lsm command.
An --omit-url flag can be used to omit it (e.g. if generating one on
a very large LSM is too slow).

[cockroach-teamcity]

This change is 

[jbowens]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @RaduBerinde and @sumeerbhola)

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-- commits line 6 at r1:
nit: should we do the inverse of opting into the URL? or only generate the URL if it'll be reasonably sized (looks like Google Chrome allows URLs of up to 2MB)? I'm a little wary of it being slow but not knowing that there's an --omit-url flag to make it fast.

[sumeerbhola]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @jbowens and @RaduBerinde)

[RaduBerinde]

Reviewable status: 0 of 2 files reviewed, 1 unresolved discussion (waiting on @jbowens)

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-- commits line 6 at r1:

Previously, jbowens (Jackson Owens) wrote…

nit: should we do the inverse of opting into the URL? or only generate the URL if it'll be reasonably sized (looks like Google Chrome allows URLs of up to 2MB)? I'm a little wary of it being slow but not knowing that there's an --omit-url flag to make it fast.

Yeah I agree, done.