Initial commit for new, C++-based webapp research prototype

:P
Some pointless beginning.
JSON writer should be almost complete.
Url parsing infrastructure
Addec libcurl dependency and enhanced Url parser
Better URL parser; some more config functions
Some important fixes in Url/JSONObject. Unit tests.
IPC/Transactions for webapp.
First request handlers installed
Fixed at least three severe bugs.
Some more requests implemented
All request types implemented.
Webapp-CPP is working.

Performance test:
    * Sending messages - ~550 msgs per second (steadily)
    * isonline requests: 3500 requests per second (steadily)
Merge branch 'webapp-cpp'
Fixed memory issue in savedmessages response handler
Small documentation updates