Added Functions Query and Function Score Query

[janaculenova]

Hi, I asked for weight function and function_score with multiple fields few weeks ago.

• Added Functions Query with weight function (it's possible add more functions)
• Added Function Score Query

[erichard]

Hi ! Thanks for the PR and sorry for the delayed review :pray:

Can you add some tests please ?

[janaculenova]

Sure! I'm a bit busy these days, but I'll try dedicate some day next week.

[janaculenova]

Hi @erichard I commited tests

[erichard]

Thanks @janaculenova 🙏