make consistent module placing

[ppanero]

invenio-records-resources defines a file/module hierarchy base on layers (records, services, resources). Then inside each one of them are the specifics for each record type (e.g. communities, members, etc.). This module has a mix between an inverse approach defining root modules for record types (communities, members) and then inside each of them the layers. Additionally, there is a records module in the root which is confusing, a schema.py (services) and resolvers (should be records data access layer) file in the root of communities which should be in the services layer, permissions.py in the root instead of in the /services...

TL;DR: needs mass file placement refactoring

/resources
|
|- /communities
|- /members 

/services
|
|- /communities
|- /members 

/records
|
|- /communities
|- /members