Although this doesn't change much for our specific case, it can make a
difference for some flags, so use the appropriate macro.

it. It seems to only be available on recent (>=4.6) versions of gcc.

now translated if set to a button

All usages of gettext() are converted to wchars, so let's factor this
into a single inline.

Fixes a bug that made the server to deny non-empty passwords from players connecting the first time.

Fixed handling of inventory in creative mode (normal inventory is not trashed anymore), fixed mese pick speed, added some forgotten stuff

set locales to C because en_US not installed on some systems, only UTF-8 version and en_US.UTF-8 does not work.