Storyshots advanced config options

[igor-dv]

Issue: #3260

This PR is rebased on "storyshots-refactoring" branch because I didn't want to wait for the #3745 to be merged.

What I did

1. Added an option to configure storybook inside the storyshot test.
2. configPath were only able to point on config dir, now it can also point on config.js
3. Added an optional parameter for the test functions to prevent using them like this : multiSnapshotWithOptions({})

[codecov]

Codecov Report

Merging #3747 into storyshots-refactoring will increase coverage by 0.06%.
The diff coverage is 55.81%.

@@                    Coverage Diff                     @@
##           storyshots-refactoring    #3747      +/-   ##
==========================================================
+ Coverage                   41.53%   41.59%   +0.06%     
==========================================================
  Files                         461      462       +1     
  Lines                        5128     5147      +19     
  Branches                      860      866       +6     
==========================================================
+ Hits                         2130     2141      +11     
- Misses                       2483     2490       +7     
- Partials                      515      516       +1

Impacted Files	Coverage Δ
...s/storyshots-core/src/frameworks/angular/loader.js	11.11% <0%> (-1.39%)	⬇️
...hots/storyshots-core/src/frameworks/html/loader.js	12.5% <0%> (-1.79%)	⬇️
...shots/storyshots-core/src/frameworks/vue/loader.js	0% <0%> (ø)	⬆️
...yshots/storyshots-core/src/frameworks/rn/loader.js	0% <0%> (ø)	⬆️
...yshots/storyshots-core/src/frameworks/configure.js	100% <100%> (ø)
...ots/storyshots-core/src/frameworks/react/loader.js	100% <100%> (ø)	⬆️
...ts/storyshots-core/src/frameworks/config-loader.js	100% <100%> (ø)	⬆️
...dons/storyshots/storyshots-core/src/test-bodies.js	90.47% <100%> (ø)	⬆️

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