[reSIProcate] What is the difference between PlainContents and GenericContents classes ?

[priya g. ranjan]

Hello, 
 
I am looking at the reSIProcate parsing code design. I did not understand the difference in the classes - PlainContents and GenericContents. The behavior of the two classes seemed identical, and there were no other sub-classes inheriting from PlainContents. 
 
Thanks,
- Ranjan