The ObjectStream classes now read and write strings as StringRefs

Be warned: this has changed the stack loading/saving code. Although it has been tested for both loading and saving, care should be taken.
Merge branch 'refactor-syntax_unicode' into refactor-syntax_unicode_objectstream
Move string translation from MCObject::load into MCObjectInputStream
Merge remote-tracking branch 'upstream/refactor-syntax_unicode' into refactor-syntax_unicode_objectstream

Conflicts:
	engine/src/object.cpp
Merge remote-tracking branch 'upstream/refactor-syntax_unicode' into refactor-syntax_unicode_objectstream
Merge remote-tracking branch 'upstream/refactor-syntax_unicode' into refactor-syntax_unicode_objectstream
Update to return IO_ERROR on certain failures
Fixed forgotten code which caused constant error throwing
Merge remote-tracking branch 'upstream/refactor-syntax_unicode' into refactor-syntax_unicode_objectstream
Fixes
Memory leak fix
[[ Unicodify ]] Fix incorrect free in dskmac.cpp GetCurrentFolder.
Make the script editor work again
Removed MCStringGetCString calls from the files below
Fixed a memory leak
Removed some more MCStringGetCString calls.
Updates on mblandroid* files (removed MCStringGetCString calls)
deleted test.rev file, and now it compiles
reverted changes in mblandroidcalendar.cpp (MCLog functions are left with MCStringGetCString), and deleted test.rev so as to compile
Updates after Mark's feedback