Service has once service_title so that as a column

Replacing service_attr table and its joins
Service categories - many to many

There is a many to many relationship between services and categories so
represent this as a separate table.
Handle 'other' category

For plugins without a category or those than mention category explicitly
Populate service_title from graph_title
Subgraphs is just a column of services
graph_info is just a column of services
fetch multiple service infomation all in one go
syntax fixes
Merge pull request #276 from openquery/service_attr

Service - remove some common attributes and handle more like sql