Initial starting point
Complete lower layer with tests and samples
fix the Readme
Fix incorrect comments in a sample
Initialize topicString bug #427181
Add documentation, fix parameter and variable names
Comment out unused labels to eliminate compiler warnings
add contributing file
Short form of about.html
Latest updates from mbed - pings, and some fixes
Don't declare functions if no tracing needed
Bug: 434081
Move current source to the MQTTPacket subdirectory - other sub-projects coming
Add C++ embedded layer above MQTTPacket
Fix some types
Add 'libraries/mqtt/' from commit '8574f50700d865e8da7eeebfc74b1a6b649e155c'

git-subtree-dir: libraries/mqtt
git-subtree-mainline: 9b01d795ecaaf657399dc4888f30f3898d91d74a
git-subtree-split: 8574f50700d865e8da7eeebfc74b1a6b649e155c
Gongobot checkpoint