Proposal: 8355572: Implement Range header support for jwebserver

[Daisuke Yamazaki]

Hello all,

I would like to work on implementing Range header support for jwebserver,
related to JDK-8355572.
Before I start working on it, i'd like to confirm whether it's okay for me to
take this issue.

Here's my current design idea:

1. Introduce a RangeEntry record inside FileServerHandler to represent 
each requested range
2. In FileServerHandler.serveFile(), detect the Range header and parse it into
 a list of RangeEntry objects.
  If parsing fails or the range is invalid, return 416 Range Not Satisfiable.
3. If multiple ranges are specified, generate a random boundary 
string and return a multipart/byteranges response.

Please let me know if it’s okay for me to proceed with this implementation,
or if there are any design points I should consider before starting.

Thanks,
D. Yamazak