permit the RollPlugin to accept a min

[danlangford]

the ability for the roll to have a minimum value. something like <roll 1d4-2 min=0>

note that this is distinctly different then rerolling low numbers and requiring a minimum (as is suggested by Roll20 users)

in my proposal a roll of 1d4-2 would produce

raw	with min
-1	0
0	0
1	1
2	2

note the 50% chance to get a 0.

and note the rerolling approach from Roll20 forums would ensure that you roll at least a 0 by turning the -1 into a reroll with equal chance on all numbers. so there would only be a 33% chance to roll a 0.

my proposal fits with a handful of D&D rules that state a hard minimum instead of a reroll.

Each time you gain a level, you gain 1 additional Hit Die. Roll that Hit Die, add your Constitution modifier to the roll, and add the total (minimum of 1) to your hit point maximum.