/rs search <itemId> [<gpssearch>] : use compass like a gps to search a shop where you can buy an item
<gpssearch> is the result number from the /rs search <itemId> result list.
Set <gpsearch> to "off" to set the compass back to the spawn
fixed damaged items buy / sell NPE crash
get back shopInfiniteBuy and shopInfiniteSell default values for those flags into config.txt (default to false)
added enchantmentLevelRatio, enchantmentRandomWeightRatio to set ratios for enchanted items into config.txt (default to 1.1 for both of them)
