* Start installing the SQLite store and bootstrapping the datom store.
* Review comment: Decomplect V2_IDENTS.
* Review comment: Decomplect V2_PARTS.
* Review comment: Pre: Expose Clojure's merge on Value instances.
* Review comment: Decomplect V2_SYMBOLIC_SCHEMA.
* Review comment: Decomplect V1_STATEMENTS.
* Review comment: Prefer ? to try!.
* Review comment: Fix typos; format; add TODOs.
* Review comment: Assert that Mentat `Schema` is valid upon creation.
* Review comment: Improve conversion to and from SQL values.
This patch factors the fundamental SQL conversion maps
between (rusqlite::Value, value_type_tag) and (edn::Value, ValueType)
through a new Mentat TypedValue. (A future patch might rename this
fundamental type mentat::Value.)
To make certain conversion functions infallible, I removed
placeholders for :db.type/{instant,uuid,uri}. (We could panic
instead, but there's no need to do that right now.)
* Review comment: Always uses bundled SQLite in rusqlite.
This avoids (runtime) failures in Travis CI due to old SQLite
versions. See 432966ac77.
* Review comment: Move semantics in `from_sql_value_pair`.
* Review comment: DB_EXCISE_BEFORE_T instead of ...BEFORET (no underscore).
* Review comment: Move overview notes to the Wiki.
