Create cache interface to store frequently accessed I/O bound data

[kyujin-cho]

After #1911 is resolved, we need to think about implementing cache interface to store frequently accessed, I/O bound datas. API responses from Harbor API will fall into this case. Interface must be designed in a way to utilize heterogeneous cache backends, but for now let's just think of using only one cache backend, redis.

[achimnol]

Just an idea: Could we consider some build-artifact caching solutions (like what Pantsbuild uses...)?