Add schema to doctrine:enum:drop-comment

[mpescadorsantirso]

As Feature request in command "doctrine:enum:drop-comment" will be nice autodetect schema in line 167 replace:

$tableName = $metadata->getTableName();

for something like:

$tableName = $metadata->getSchemaName().".".$metadata->getTableName();

I think this is important because not all of us will be using "public" schema.