adding artifacts to CI

[aviadingo]

using precompiled versions stored in artifacts.

whenever CI is triggered it does the following:

1. checks cache to see if it has a precompiled version of the backend.
2. if there isn't any: checks the artficat repository for a precompiled version
3. if there isn't ant: builds the backend and stores it in cache & artifacts.

this support future precompilation using gh servers