This function is not useful inside ovsdb itself but only in the
"test-ovsdb" test program. To avoid the temptation to use it incorrectly
inside ovsdb, this commit moves it into the test program.
Using a separate XML file to document a schema is much more flexible.
You end up with two files (a schema and documentation for it), each of
which is readable and maintainable, instead of a single schema file that
is almost illegible.
There is no value in saving a call to uuid_hash() in ovsdb_table_put_row(),
because uuid_hash() is a trivial inline function, so integrate
ovsdb_table_get_row__() into ovsdb_table_get_row() and simplify
ovsdb_table_put_row().
Until now, when a transaction modified rows in a table, the metadata
associated with that table modification (in struct ovsdb_txn_table) had to
be looked up through a hash table. This made the code unnecessarily
complicated and had no benefit in itself, so this commit changes
struct ovsdb_table to have a direct pointer to its ovsdb_txn_table.
Database, table, and column names have always been required by the OVSDB
specification to be identifiers (e.g. valid C identifiers), but this has
never been enforced.
This commit adds enforcement and fixes one instance of an invalid column
name in the vswitch schema.
