StatsPerform JSON parsers: load data from memory

[denisov-vlad]

Current loaders is designed to read files and process them into dataframes.

It's not suitable if you want to use SDDP feed instead of SDAPI. The difference is that SDDP adds events during the match and SDAPI is available only after match.

I want to calculate some metrics during the match and created alternative memory loader based on MA3 Loader:
https://gist.github.com/denisov-vlad/28d4668c4861b7c551a6caba3c341ba2

As you see, there is a lot of duplicated code. It will be awesome to split extract functions into loading from disk and processing data.