Actually fix weather

The real problem was that MapBlocks were not activated before getting sent to the client
Decoration: Stop DecoSimple::resolveNodeNames from complaining about no node name if decolist is used

Fix warning message for spawnby nodes

Prevent type-punning warning caused by casting enum to int
Don't use msvc libs for mingw build
Add CURL_DLL search to show up CURL_DLL in cmake gui and don't silently ignore missing CURL_DLL
Prevent shaders from being created when disabled
Replace print()s with minetest.log() in builtin
Revert "Don't use msvc libs for mingw build"

This reverts commit 3985c01ad71159b888677d0fe2019d7a05debeed.
Handle blank blocks in database

Fix screwed-up indentation
Do the same for LevelDB interface
Fix multicaller support in RequestQueue
Add missing RequestQueue doc
Fix Result of processed Request was written to invalid (non existent) ResultQueue if requesting thread timed out before
Merge remote-tracking branch 'upstream/master' into dynamic

Conflicts:
	src/environment.cpp
	src/map.cpp