Enable decimals for custom prioritisation formula Merged

Our team uses the RICE prioritization formula, and we want to be able to assign the following values

a) Reach:

• 1: internal users only

• 1.5: user group non key decision maker for our product

• 2: user group key decision maker for our product
  

Hence using decimals.

b) Confidence:

we want to be able to assess confidence on a scale of 0.1 to 1, so that when the confidence score is multiplied for RI(reach + impact), a lower confidence will decrease the impact score.