Small suggestions collected from the bug reports

[Narc]

(in no particular order, i.e. the order I found them in)

• Inserter behaviour should be configurable (insert minimum, insert maximum). First seen in Inserter to Boiler issues.
• Pipes (at least) should have a more obvious way of checking the liquid pressure inside. First seen in Steam engines and underground interaction.

If there are any more, post them here. Hopefully keeping the suggestions and bug reports separate will help things never get lost.