(feat) Query builder

[thomasht86]

I confirm that this contribution is made under the terms of the license found in the root directory of this repository's source tree and that I have the authority necessary to make this contribution on behalf of its copyright owner.

Consider this a first draft, and I can go through it tomorrow.

To discuss:

• Should we allow for using kwargs for annotations - good for some, but many annotations are camelCase - does not good in python.
• Rename Q and G- to what?

TODO:

• Integration test for grouping

[thomasht86]

TODOs after review:

• Rename querybuilder/main.py. Check if there is a convention. If not, querybuilder.py
• Queryfield -> QueryField
• maybe use qb condition.
• Describe how to build many queries programmatically (need to copy)
• snake case for eg groupBy - dotProduct.
• grouping to its own module