Ultimately this is going to be a tool that can generate nicely-formatted
spreadsheets from arbitrary bean-queries. This initial version doesn't
generate spreadsheets yet, but it does integrate our usual books-loading
tools and rewrite rules into existing bean-query functionality, so it's a
start. It also has some of the query building and parsing that higher-level
spreadsheets will need.
This loads settings from the same environment variables and ~/.rtrc
file as the rt CLI.
Note that it does *not* support RTCONFIG and the config file
searching, because right now that seems like more work for more
trouble to me.
