Thinking about contributing some docs changes, but it's my first contribution
so I thought I'd discuss it first.
1. Pull out mango querying information into its own user guide--it's a pretty
complex topic, with a DSL, new database concepts (indexes), and some
interactions with other concepts that should maybe be written down. It's
currently buried between /{db}/_find, /{db}/_index, intuition, and
experimentation.
2. Put a note somewhere that while documents with fields that are empty or
start with _ and $ are technically allowed, they will interact badly with mango.
I'm extremely familiar with Sphinx, so I don't need mentoring in that regard. I
just wanted to touch base with the devs before re-organizing a bunch of stuff
and writing 5000 words.
