Enhancement: Support viewer needs two kinds of compression

[awkay]

Transmitting a support request is currently very expensive. We could compress history into a single snapshot followed by a sequence of diffs (one per tx).

The second kind of compression needed is being able to mark a transaction as "skippable", primarily for form-text input (e.g. every keystroke makes a new history entry). The rules would be: two or fewer adjacent "skippable" entries are left alone. Three or more cause all the "middle ones" to not be recorded at all such that you always end up with one or two "skippable" entries in history for any sequence. The first (and only) is the "one" case. The first and last are the "many" case.

Implementation-wise, this is essentially "overwrite the last history entry if that entry is skippable and the prior entry is ALSO skippable".

Might be nice to get this latter bit into Om as a PR somehow.