Hummingbird marketplace modifications

[rohrerj]

Includes:

• Support for combining multiple assets into one asset in a single request
• Support for splitting an asset into multiple assets
• Introduced the time_max_duration the limit the maximum allowed reservation duration of an asset
• Pagination for the search assets endpoint
• Updated reservation id interval for redemption delegations to allow for intervals not starting at 0
• Introduction of an Asset Even table to fix some problems with calculation of AS asset statistics

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This change is