Add docs and specs

x/group/README.md

@@ -109,6 +109,16 @@ A threshold decision policy defines a threshold of yes votes (based on a tally
 of voter weights) that must be achieved in order for a proposal to pass. For
 this decision policy, abstain and veto are simply treated as no's.
 
+This decision policy also has a VotingPeriod window and a MinExecutionPeriod
+window. The former defines the duration after proposal submission where members
+are allowed to vote, after which tallying is performed. The latter specifies
+the minimum duration after proposal submission where the proposal can be
+executed. If set to 0, then the proposal is allowed to be executed immediately
+on submission (using the `TRY_EXEC` option). Obviously, MinExecutionPeriod
+cannot be greater than VotingPeriod+MaxExecutionPeriod (where MaxExecution is
+the app-defined duration that specifies the window after voting ended where a
+proposal can be executed).
+
 #### Percentage decision policy
 
 A percentage decision policy is similar to a threshold decision policy, except
@@ -117,6 +127,9 @@ It's more suited for groups where the group members' weights can be updated, as
 the percentage threshold stays the same, and doesn't depend on how those member
 weights get updated.
 
+Same as the Threshold decision policy, the percentage decision policy has the
+two VotingPeriod and MinExecutionPeriod parameters.
+
 ### Proposal
 
 Any member(s) of a group can submit a proposal for a group policy account to decide upon.

x/group/types.go

@@ -32,7 +32,8 @@ type DecisionPolicy interface {
 	// votes are accepted.
 	GetVotingPeriod() time.Duration
 	// GetMinExecutionPeriod returns the minimum duration after submission
-	// where we can execution a proposal.
+	// where we can execution a proposal. It can be set to 0 or to a value
+	// lesser than VotingPeriod to allow TRY_EXEC.
 	GetMinExecutionPeriod() time.Duration
 	// Allow defines policy-specific logic to allow a proposal to pass or not,
 	// based on its tally result, the group's total power and the time since