Guess main socket group based on dps + Full import button

[Musholic]

Description of the problem being solved:

This PR allows to have a one-button full import while allowing to better guess which socket group is the main one based on DPS calculations of all groups. It also includes the main skill in Full DPS.

Note that if we cannot import with only one button, it causes an issue where the variable mainSkillEmpty = #self.build.skillsTab.socketGroupList == 0 is false because there is a skill coming from the tree ("Called shots" in my case).

This is also useful for the automatic test I'm preparing to have more relevant tests (having a skill correctly included for the full dps stats) (Musholic#11).

• I tested the performance on a simple character import (it was very fast), however it needs to be tested on more complex characters before we merge this PR
  • There was some tests done by LocalIdentiy at the time the PR was made with no significant performance impact (around 130ms max delay). There is a possible performance improvements to skip check on non damaging skills but it needs a reliable way to tell if a skill is non damaging.

Steps taken to verify a working solution:

• Tested with my lvl 35 character

Before screenshot:

After screenshot:

[Musholic]

The PR is rebased and ready to be merged IMO, I updated the description regarding the performance tests