1) Getting vega specification

a) getting the base
empty -> for empty graphs
default -> for other graphs

b) getting the body
barchart / linechart / multilinechart / windchart

c) getting the legend specification

d) getting the tooltip specification
(samm -> sum, avg, min, max)

e) merging the files into result


2) Vega configurations.

Process of getting configuration:
a) gets config.json
b) gets other config file for corresponding graphs
c) merge signals array from other graph to config.json

(barline = bar + line)

note: config signals typically contain path to values

