Make these modules' names more like the heavily-used types they
define (CliOpts, UIOpts, WebOpts). This is consistent with
RawOptions and ReportOptions, and helps with code navigation.
Here are hpack package.yaml files for the other hledger cabal files.
These remove a lot of human-error-prone duplication.
They are not used yet as hpack isn't quite mature enough -
when it supports flags and benchmarks we will probably switch.
