Array manipulation functions v10

• added array_sort()
  
• added array_rsort()
  

• made array_shuffle() significantly faster
  
• added array_filter()
  

• made array_reverse() faster
  
• added array_diff()
  

• added optional <neq> parameter to array_replace()
  
• added optional <neq> parameter to array_find()
  
• added optional <neq> parameter to array_rfind()
  
• added optional <neq> parameter to array_exists()
  
• added optional <neq> parameter to array_count()
  
• added array_entries()
  

• removed some superfluous variables
  
• fixed a bug in array_unshift that happens when used with non-zero index
  
• array_shuffle now shuffles only from the index to the end instead of the whole array
  

• replaced absolute value calculation in array_pad() by a less expensive approach
  

• added array_unique()
  

• added array_shuffle()
  

• made all commands accept any index
  
• added array_shift()
  
• added array_unshift()
  
• added array_pop()
  
• added array_push()