Primary API for HoneySQL 2.x.

This includes the `format` function -- the primary entry point -- as well
as several public formatters that are intended to help users extend the
supported syntax.

In addition, functions to extend HoneySQL are also provided here:
* `clause-order` -- returns the current clause priority ordering;
      intended as aid when registering new clauses.
* `format-dsl` -- intended to format SQL statements; returns a vector
      containing a SQL string followed by parameter values.
* `format-entity` -- intended to format SQL entities; returns a string
      representing the SQL entity.
* `format-expr` -- intended to format SQL expressions; returns a vector
      containing a SQL string followed by parameter values.
* `format-expr-list` -- intended to format a list of SQL expressions;
      returns a pair comprising: a sequence of SQL expressions (to be
      join with a delimiter) and a sequence of parameter values.
* `register-clause!` -- register a new statement/clause formatter.
* `register-fn!` -- register a new function call (or special syntax)
      formatter.
* `register-op!` -- register a new operator formatter.
* `set-dialect!` -- set the default dialect to be used for formatting,
      and optionally set a global `:quoted` option.
* `sql-kw` -- turns a Clojure keyword (or symbol) into SQL code (makes
      it uppercase and replaces - with space). 

  (-> (select :a :b :c)
      (from :table)
      (where [:= :id 42])
      (sql/format))

  (-> {}
      (select :a :b :c)
      (from :table)
      (where [:= :id 42])
      (sql/format))

bulk-collect-into [varname] [varname n]

bulk-collect-into [dsl varname] [dsl varname n]

bulk-collect-info [& args]

Helper functions for the built-in clauses in honey.sql.

  All helper functions are inherently variadic. Typical
  usage is threaded, like this:

```
  (-> (select :a :b :c)
      (from :table)
      (where [:= :id 42])
      (sql/format))
```

  Therefore all helpers can take an existing DSL expression
  as their first argument or, if the first argument is not
  a hash map, an empty DSL is assumed -- an empty hash map.
  The above is therefore equivalent to:

```
  (-> {}
      (select :a :b :c)
      (from :table)
      (where [:= :id 42])
      (sql/format))
```

  Some of the helper functions here have `:arglists` metadata
  in an attempt to provide better hints for auto-complete in
  editors but those `:arglists` _always omit the DSL argument_
  to avoid duplicating the various argument lists. When you
  see an auto-complete suggestion like:

    bulk-collect-into [varname] [varname n]

  bear in mind that a DSL hash map can always be threaded in
  so the following (pseudo) arities are also available:

    bulk-collect-into [dsl varname] [dsl varname n]

  The actual arguments are:

    bulk-collect-info [& args]

  (as they are for all helper functions).

Register all the PostgreSQL JSON/JSONB operators
and provide convenient Clojure names for those ops.
In addition, provide names for the PostgreSQL
regex operators as well.

For the eleven that cannot be written directly as
symbols, use mnemonic names: hash for #, at for @,
and tilde for ~.

For the six of those that cannot be written as
keywords, invoke the `keyword` function instead.

Those latter eight (`at>`, `<at`, `at?`, `atat`,
`tilde`, `tilde*`, `!tilde`, and `!tilde*`) are
the only ones that should really be needed in the
DSL. The other names are provided for completeness.

`regex` and `iregex` are provided as aliases for the
regex operators `tilde` and `tilde*` respectively.
`!regex` and `!iregex` are provided as aliases for the
regex operators `!tilde` and `!tilde*` respectively.