[zaneal34]

Implements issues #58, #59, #63, and #64 in a single PR.

Changes

• Issue Let a subscriber lower a subscription's cap, never raise it #58: Add lower_cap() to allow subscribers to reduce subscription caps
• Issue Add a get_admin view to the subscription and plan contracts #59: Add get_admin() view to subscription and plan contracts
• Issue Add get_plan_count and a plans-by-token index #63: Add plan-by-token indexing with get_plan_count() and get_plans_by_token()
• Issue Add version() to the plan and registry contracts #64: Add version() functions to plan and registry contracts

All changes are thoroughly tested and make check passes.

Closes #58
Closes #59
Closes #63
Closes #64

[drips-wave]

@zaneal34 Great news! 🎉 Based on an automated assessment of this PR, the linked Wave issue(s) no longer count against your application limits.

You can now already apply to more issues while waiting for a review of this PR. Keep up the great work! 🚀

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