Bugfix: minimap was updated only with loading new blocks, allow forced updates with changing player pos

Add missing check for max_stone_y to mgv5 cavegen
Tunnels now carve through sand below water_level

Thanks @TeTpaAka for pointing this out.

Fix grammar error and missing number conversion for version.
Also add deployed protocol to log line.

Improve shift+click experience

-> remove the old parent as @kahrl suggested
-> use indices no iterator as @kwolekr suggested

* Use enum for GENERIC_CMD_*
* Rename m_attachements to attachement_parent_ids (public member and clearer name)
* Rename GENERIC_CMD_SET_ATTACHMENT to GENERIC_CMD_ATTACH_TO
* USHRT_MAX + 1 buffer sizes to prevent overflows as @kahrl suggested
* Remove unneccessary m_id from GenericCAO (shadowing protected superclass member for no reason) as @kahrl suggested

Also fix UTF-8 inner byte bounds and make unittest for case this fixes.

Also count multibyte sequences as "one" character.
Adds unittest for the bug reporter's case.
Fixes #2796.

No freezing when inbuf_size doesn't decrease over time.

* Make method (more) consistent with current code stlye
* Move index into loop constructor after @rubenwardy's suggestion
* Cache inv_s->getList(s.listname), which removes a possibly bad scenario
of inv_s being null.
* Properly check for validity

Adds list-rings, a method to implement item sending between inventories via shift-click.
Nice insider feature: a ring consisting of a single inventory list serves as nice clean-up method.
Also adds them to minimal game, and the standard inventory.
Craft output slots are not supported.

Decorations: Remove lower limit of water level for placement

While utf8_to_wide works well, wide_to_utf8 is quite broken
on android, for some reason.