Reduce the execution time of maven-antrun-plugin

Related issue: #2508

Motivation:

The '<exec/>' task takes unnecessarily long time due to a known issue:

- https://issues.apache.org/bugzilla/show_bug.cgi?id=54128

Modifications:

- Reduce the number of '<exec/>' tasks for faster build
- Use '<propertyregex/>' to extract the output

Result:

Slightly faster build
Fix data corruption in FileRegion transfer with epoll transport

Related issue: #2764

Motivation:

EpollSocketChannel.writeFileRegion() does not handle the case where the
position of a FileRegion is non-zero properly.

Modifications:

- Improve SocketFileRegionTest so that it tests the cases where the file
  transfer begins from the middle of the file
- Add another jlong parameter named 'base_off' so that we can take the
  position of a FileRegion into account

Result:

Improved test passes. Corruption is gone.
Fix and clearify javadocs

Motivation:

ByteToMessageDecoder and ReplayingDecoder have incorrect javadocs in some places.

Modifications:

Fix incorrect javadocs for both classes.

Result:

Correct javadocs for both classes
Rename FastLzFramed* to FastLzFrame*
Fix class description of FastLzFrameDecoder
[#2768] Correctly duplicate buffer for CloseWebSocketFrames

Motivation:

The _0XFF_0X00 buffer is not duplicated and empty after the first usage preventing the connection close to happen on subsequent close frames.

Modifications:

Correctly duplicate the buffer.

Result:

Multiple CloseWebSocketFrames are handled correctly.