Add explicit renameColumn method for Table

[Tofandel]

Q	A
Type	feature
Fixed issues	doctrine/migrations#57

Summary

Add a renameColumn in the Table class

This allow to create migration with schemas that rename columns explicitely, which is a missing feature

Right now only implicit detection is done (it looks for added columns with the same definition as a dropped column), and that means if you change an option or the type of the column, it will not consider it as a rename anymore and instead will drop and recreate, by being explicit, this is not a problem anymore

This PR allows the following migration, without losing the column data

    public function up(Schema $schema): void
    {
        $schema->getTable('test')->renameColumn('foo', 'bar')->setType(Type::getType('text'));
    }
    
    public function down(Schema $schema): void
    {
        $schema->getTable('test')->renameColumn('bar', 'foo')->setType(Type::getType('string'));
    }

Which before would have to drop the column and recreate it, as well as needing a full redefinition of the column, and losing the data in the process

    public function up(Schema $schema): void
    {
        $schema->getTable('test')->dropColumn('foo')->addColumn('bar', 'text');
    }
    
    public function down(Schema $schema): void
    {
        $schema->getTable('test')->dropColumn('bar')->addColumn('foo', 'string');
    }

PS: I'm building a feature for the doctrine/migration package to generate diffs of schema, directly using Schema instead of platform specific sql and without this renameColumn this would be impossible

[derrabus]

Thank you. We don't accept features on the 4.0.x branch. Please target 3.7.x.