copy property alias attributes from the pointed-to properties

Change and test how the engine and qmltc handle alias attributes.

Some terminology:

property alias aliasingProperty: someobject.aliasedProperty

Following attributes exists:

• READ, WRITE, MEMBER
  • copy those attributes from aliasedProperty
• RESET:
  • copy attribute from aliasedProperty
• NOTIFY:
  • copy attribute from aliasedProperty
• REVISION:
  • copy attribute from aliasedProperty
• DESIGNABLE:

• • copy attribute from aliasedProperty
• SCRIPTABLE:

• • should always be true
• STORED:
  • should always be false
• USER:
  • should always be false
• BINDABLE:
  • copy attribute from aliasedProperty

• CONSTANT:
  • copy attribute from aliasedProperty
• FINAL:
  • should always be false
• REQUIRED:
  • should always be false