Headline Features

(#156) Implement non-duffer pruning. In short, you specify courses which are 'non-duffer' (e.g.
those with 4-bell runs) and then you can enforce a limit on how much contiguous/total 'duffer'
rows can be rung. Think MBD's no-duffer Bristol, but this works for any composition.
(#143) Use explicit memory limit. Set by --mem-limit or -M, defaults to ~~90%~~ 80% of
available system memory.

Internal Improvements

(#165) Only require clippy lints on releases.
(#146) Merge fields of graph::build::MethodData into query::Method.
(#142) Implement builder API to make monument easier to use as a library
(#142) Make Query private and build Searches directly.
(#140) Rename some fields of Query (which, after #138, are no longer exposed externally)
(#138) Heavily clean up the API of the monument library. This PR focusses on removing as much
API surface as possible, so that the remaining API can be made as easy as possible to use. With
some more attention, it should be possible to embed the monument library into programs other
than its CLI interface.

(these are bugs which were created during this release, so were never public)

(#166) Output correct contiguous duffer lengths in multi-parts.
(#166) Make Chunks non-duffer only if they are a non-duffer in every part.
(#145) Reduce memory limit from 90% to 80% of the available memory.

(#140) Rename Mask::fix_bells to Mask::with_fixed_bells.
(#140) Don't return borrowed data in the error from MethodLib::get_by_title_with_suggestions.
(#156) Only implement Add/Sub for Bell with i16 (i.e. not u8 or i8). If you want to
add/subtract Bells with i8 or u8, cast them to i16.
(#156) Add Method::lead_end (to complement Method::lead_head).
(#156) Add Mask::from_{bells,vec} and Mask::bells.