Fix for partial TCPClient readings

Added total buffered size to compare offset
Update spark_wiring_tcpclient.h
Update spark_wiring_tcpclient.cpp
Update spark_wiring_tcpclient.h

I had 16 hard coded one place in my local code. Now it should work straight from Github base.
Updated README to mention dfu-utils version
Merge pull request #67 from weakset/master

Fix for missing readings with TCPClient
Merge pull request #69 from theicfire/master

Updated README to mention dfu-utils version
Merge pull request #68 from davids5/master

Allow the use of Jtag independent of DFU_BUILD Support for build with CodeSourcery