a lot just add inherited members so links to things like SelectBase.cte
continue to function

Change-Id: Ib57948d576d2063e10b0f528a5deaf07ea262322

The TABLESAMPLE clause allows randomly selecting an approximate percentage
of rows from a table. At least DB2, Microsoft SQL Server and recent
Postgresql support this standard clause.

Fixes: #3718
Change-Id: I3fb8b9223e12a57100df30876b461884c58d72fa
Pull-request: https://github.com/zzzeek/sqlalchemy/pull/277

Also add doc members for Lateral.

Change-Id: Ic801c296377ce84230139c6a43ecb3e93a852832

for the SQL standard LATERAL keyword, currently only supported
by Postgresql.  fixes #2857

INSERT, UPDATE, and DELETE statements to both specify their own
WITH clause, as well as for these statements themselves to be
CTE expressions when they include a RETURNING clause.
fixes #2551

method, and its interaction with result-row processing, now allows
the columns passed to the method to be positionally matched with the
result columns in the statement, rather than matching on name alone.
The advantage to this includes that when linking a textual SQL statement
to an ORM or Core table model, no system of labeling or de-duping of
common column names needs to occur, which also means there's no need
to worry about how label names match to ORM columns and so-forth.  In
addition, the :class:`.ResultProxy` has been further enhanced to
map column and string keys to a row with greater precision in some
cases.  fixes #3501
- reorganize the initialization of ResultMetaData for readability
and complexity; use the name "cursor_description", define the
task of "merging" cursor_description with compiled column information
as its own function, and also define "name extraction" as a separate task.
- fully change the name we use in the "ambiguous column" error to be the
actual name that was ambiguous, modify the C ext also

to the aliasing syntax, as well as a new CTE feature
:meth:`.CTE.suffix_with`, which is useful for adding in special
Oracle-specific directives to the CTE.
fixes #3220

more flexible ways to set up bound parameters and return types;
in particular, a :func:`.text` can now be turned into a full
FROM-object, embeddable in other statements as an alias or CTE
using the new method :meth:`.TextClause.columns`.
[ticket:2877]