Replace raw Sequel API with Lotus::Model

[jdickey]

Replace raw Sequel API with Lotus::Model

[jdickey]

One big win here should be an ability to use in-memory adapters for non-integration/"feature" test code, essentially eliminating the largest single drag on test performance.

This does require the replacement of our current Sequel::Model-based Thing model with the various concepts implemented by Lotus::Model (or any Data Mapper pattern implementation): an Entity, Repository, Data Mapper, and possible Query (replacing the existing Thing.for_index pseudo-scope query).

Although this is a significant expansion in scope from that described in the original README, the benefit of developing this highly-desirable capability in the context of a project with a single, simple data model seems to outweigh the natural (and principled) reticence regarding such an expansion.

Release 0.9.1 of the app was tagged early on 31 December 2015, at which time the schedule for tagging a 1.0 release was deferred until 8 January 2016 (from 1 January). I propose that that date (8 January) serve as a deadline for this feature; if it can be included as part of a 1.0 release, well and good; otherwise, it will be deferred. Therefore, the issue will not immediately be assigned to a milestone more specific than The Glorious Future.

[jdickey]

It should also be noted that using Lotus::Model does not imply any further commitment to the rest of the Lotus framework; Lotus::Model has been demonstrated in use with Rails and other frameworks besides Lotus (e.g., Padrino). We would brand those who argue for the presence of a "slippery slope" in that regard as optimists.

[jdickey]

Lotus is now Hanami, and Lotus::Model is now Hanami::Model. One of the major contributors recently commented:

… we are in the cycle of improving model so please stay tuned.

Pending the dust re-settling on Hanami::Model, this issue is remaining as it is: consigned to The Glorious Future™, without an assigned developer or deadline.