read_file() used to append a new line character to the end of the buffer it
returns, because parse_config() isn't able to cope with input that's not
'\n'-terminated. Fix read_file() to be less insane, and push the workarounds
into the parse_config() callers.
Longer term we should rewrite parse_config().
Change-Id: Ie9d9a7adcd33b66621726aef20c4b8cc51c08be7
This isn't particularly useful in and of itself, but it does introduce the
first (trivial) unit test, improves the documentation (including details
about how to debug init crashes), and made me aware of how unpleasant the
existing parser is.
I also fixed a bug in passing --- unless you thought the "peboot" and "pm"
commands were features...
Bug: 19217569
Change-Id: I6ab76129a543ce3ed3dab52ef2c638009874c3de
