added operator overload to write char in StringOutputStream

Change-Id: Ie97666128a6e9ff51e30c316ed8ba52422b2000c
Make Sprintf return number of characters written

Change-Id: I19d58b31746959784c86af2c16321c9f7d41ee1f
Constify internally used temp variable in tcpsocket

Allows compiler to optimise better

Change-Id: Ie8ba91e68209cce316325230f1f4a59ef46a1776
Remove mutex from socket

if needed, concurrency must be handled by code using sockets
so normal usages must not pay for uneccessary locking.

Change-Id: I0582506801d39d4e3b230199992a1d3263d766e0