Add --pull flag to control mod update strategy

[kaidaguerre]

Update stragegy:

When updating dependencies there are multiple strategies to consider:

full - check everything for both latest and accuracy
latest - update everything to latest, but only branches - not tags - are commit checked (which is the same as latest)
development - update branches and broken constraints to latest, leave satisfied constraints unchanged
minimal - only update broken constraints, do not check branches for new commits