Class MongoSchemaBuilder

Steps how schema is being built:

1. load list of all tables with complete column and keys information from the db
2. drop all (old) foreign keys that exist in the table, but does not exist in the metadata
3. create new tables that does not exist in the db, but exist in the metadata
4. drop all columns exist (left old) in the db table, but does not exist in the metadata
5. add columns from metadata which does not exist in the table
6. update all exist columns which metadata has changed
7. update primary keys - update old and create new primary key from changed columns
8. create foreign keys which does not exist in the table yet
9. create indices which are missing in db yet, and drops indices which exist in the db, but does not exist in the metadata anymore