Rework AbstractPlatform code for table and column creation

[morozov]

1. Making the $options parameter of the AbstractPlatform#_getCreateTableSQL() non-optional and marking certain keys of the CreateTableParameters array as non-optional allows to remove some if (!empty($options[...])) checks. They are always passed.
2. The $name parameter of the AbstractPlatform#getColumnDeclarationSQL() was redundant as the $column parameter always contains the column name.
3. The primary key of the CreateTableParameters array was redundant as the primary_index key already contains the whole Index definition.
4. In the AbstractPlatform#_getCreateTableSQL() method implementations of AbstractPlatform and subclasses, calls to AbstractPlatform#getColumnDeclarationListSQL() have been replaced with a foreach loop and calls to AbstractPlatform#getColumnDeclarationSQL(). The "list" method has the same implementation for all platforms and doesn't do anything than iteration. It produces a comma separated list of column declarations, which is later augmented with constraint declarations, etc. From the code organization standpoint, it's easier to operate on an array and join it once.

TODO in 4.3.x:

1. Deprecate defining primary key indexes with duplicate columns. There's no point in having the DBAL responsible for that.
2. Mark AbstractPlatform#getColumnDeclarationListSQL() as internal or deprecate (it is only used in a test that creates a temporary table in a way that it's not supposed to).
3. Backport changes from AbstractMySQLPlatform where a call to Index#getColumns() is replaced with Index#getQuotedColumns(). Not quoting column names in SQL is a bug. There's another bug that makes adding a new PK with quoted columns on MySQL not work, so we cannot test this yet.

[morozov]

This was a hack. From the SQL syntax perspective, a column name followed by the column definition (which also starts with the column name) doesn't make sense. This code worked only because the column definition was generated for a column with empty name (which is also invalid).