Fixed invalid transformation availability check
Workers directly put product for sale
Fixed building loading (in chunks)
Minor: fixed space alignment
Split character code
Cleaner code splitting around objects

An object only as one header file (e.g. world.h) but can have several
source files (e.g. world.c, world_gen.c, etc). Features implemented in
additional source files are documented in the header files.
Added methods giving orders to character

This fixes #2 where attacking the closest building or character only
made the character go to it by making orders explicit.
Added checks when attacking

This fixes #3 where a character could attack a building from within. Since
a character in a building is safe, this would have made the player unable
to defend her own house.
Fixed left click on material in own building
More compact pool using one indirection level
Isolated object removal from pool

Object removal can cause issues when performed while iterating over
the pool. Thus, the deletion operation is postponed until pool_upd()
is called, when it is safe to do so.
Fixed iterations through pool objects
Updated action messages
Updated action 'following a character'
Updated tooltips for building subwindow
Minor: added money to quickstart