Allow for opportunities

[xcampax]

Problem statement
I want to be able to record, evaluate, and track the realization of opportunities, but the current implementation only allows for risks.

Expected behavior
The existing risk management section could be reused or duplicated, with field names and values inverted.

Mock

Additional context
Ugh, I just noticed my mock-ups are messed up...

(1)
Risk assessment > Opportunity assessment
Associated risk scenarios > Associated opp. scenarios
+Add risk scenario > Add opp. scenario
Threats > Improvments

(2)
Risk matrix view > Opportunities evaluation
Likelihood > Effort
Impact > Value

(3)
Threats > Opportunities

[xcampax]

According to chapter 6.1, the addressing of opportunities is a requirement for ISO 27001. Therefore, I would consider this as an elemental function to be integrated.