Fix check of 22 artifacts limit on Altar of Sacrifice

Partially fix for issue 558
Visible blocked button for good and evil heroes on Altar of Sacrifice

This is expected behaviour as explained in issue 558
Fix check of locked artifacts for Altar of Sacrifice

This one is explained in issue 2001
Check if slot locked before pick on Artifact Merchants

This one is fixes issue 2007
Fix position of selected unit count in Freelancer's Guild

This one fixes issue 2009
Fix removal of fully sacrificed stacks from heroes garrison slots

This one fixes issue 2010. Though CAltarWindow need proper refactoring.
Put artifact in different slot if selected is used

This one fixes issue 2002.
Merge pull request #72 from ArseniyShestakov/fixTradeWindow

Small fixes for CTradeWindow