Improve emitter send data log

[Kurru]

Issue #, if available:
#26

Description of changes:
Improve the emitter sendData failure log message to include the number of bytes involved and the type of entity that failed to be published.

New log message has format:

Exception while sending segment (SegmentImpl) over UDP for entity CoreApi [1827010d1fe3a482] on segment [no parent segment]. Bytes: 77861

This code semi-frequently publishes a semi-meaningless stack trace java.net.SocketException: Message too long when the UDP packet to the daemon server is too large.

Exception while sending segment over UDP for entity CoreApi [3c2c14f28ed556d9] on segment [no parent segment]
java.net.SocketException: Message too long
at sun.nio.ch.DatagramChannelImpl.send0(Native Method) ~[?:?]
...
at sun.nio.ch.DatagramSocketAdaptor.send(DatagramSocketAdaptor.java:218) ~[?:?]
at java.net.DatagramSocket.send(DatagramSocket.java:664) ~[?:?]
at com.amazonaws.xray.emitters.UDPEmitter.sendData(UDPEmitter.java:116) ~[aws-xray-recorder-sdk-core-2.11.2.jar:?]
at com.amazonaws.xray.emitters.UDPEmitter.sendSegment(UDPEmitter.java:85) ~[aws-xray-recorder-sdk-core-2.11.2.jar:?]
at com.amazonaws.xray.AWSXRayRecorder.sendSegment(AWSXRayRecorder.java:195) ~[aws-xray-recorder-sdk-core-2.11.2.jar:?]
at com.amazonaws.xray.AWSXRayRecorder.endSubsegment(AWSXRayRecorder.java:588) ~[aws-xray-recorder-sdk-core-2.11.2.jar:?]
at com.amazonaws.xray.AWSXRay.endSubsegment(AWSXRay.java:129)

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov-commenter]

Codecov Report

Merging #343 (7828a69) into master (7e7d732) will decrease coverage by 0.01%.
The diff coverage is 0.00%.

@@             Coverage Diff              @@
##             master     #343      +/-   ##
============================================
- Coverage     58.96%   58.95%   -0.02%     
  Complexity     1207     1207              
============================================
  Files           131      131              
  Lines          5064     5065       +1     
  Branches        592      592              
============================================
  Hits           2986     2986              
- Misses         1805     1806       +1     
  Partials        273      273              

Impacted Files	Coverage Δ
...n/java/com/amazonaws/xray/emitters/UDPEmitter.java	30.55% <0.00%> (-0.88%)	⬇️

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