[10.x] Add support for getting native column type

[hafezdivandari]

Related to #45487, currently we are using Doctrine DBAL to get column type using Schema::getColumnType method. DBAL maps every native column type to its Doctrine type equivalent and doesn't support many column types used by Laravel on different databases.

This PR changes Schema::getColumnType method to return the actual column type instead of its Doctrine equivalent, also gives us the ability to write integration tests for native column modifying added on #45487. This may also be used on db:table and model:show commands.

After this PR, you'll be able to get eighter data type name or full type definition of the given column:

Schema::getColumnType('products', 'id');           // bigint
Schema::getColumnType('products', 'id', true);     // bigint unsigned
Schema::getColumnType('products', 'status');       // enum
Schema::getColumnType('products', 'status', true); // enum('active','suspended','deleted')
Schema::getColumnType('products', 'name');         // varchar
Schema::getColumnType('products', 'name', true);   // varchar(255)
Schema::getColumnType('products', 'price');        // decimal
Schema::getColumnType('products', 'price', true);  // decimal(8,2)

PS: This PR also cleans up all Schema\Builder classes, many functions were overridden without change.

[taylorotwell]

Honestly I haven't had time to fully review this PR as it's quite large - can you summarize the breaking changes in this PR?

[hafezdivandari]

@taylorotwell sure, here is the summarized list:

Added

• Added the Schema::getColumns($table) method to the schema builder.

Changed

• Changed the Schema::getColumnType method to return the native DB type instead of its Doctrine equivalent.
• Changed the processColumnListing method to processColumns method on all query processors.
• Changed the compileColumnListing method to compileColumns method on all schema grammars.
• Changed the signature of the compileTableExists method to get required arguments on all schema grammars.
• Moved createDatabase, dropDatabaseIfExists, getAllTables, and getAllViews methods from MySqlBuilder, PostgresBuilder, SQLiteBuilder and SqlServerBuilder classes to the parent Builder class without BC change.

[taylorotwell]

Tabling this for now.