Update PosSystem.java
Merge remote-tracking branch 'origin/GUI' into posSystem
Merge pull request #32 from SpyMaster356/master

update
update files
Merge pull request #39 from SpyMaster356/master

updating
added package statement
Merge pull request #40 from SpyMaster356/Customer

Customer
Merge pull request #41 from SpyMaster356/master

update
updated function calls and added hints
Merge pull request #42 from SpyMaster356/posSystem

Pos system
made phone number optional
updated PurchaceJFrame
added some comments
Merge pull request #47 from SpyMaster356/GUI

Gui