Service now can use default sendRequest function

new constructor added to Service, that sets default sendRequest function
cURLpp is now extracted to src/cURLpp/
sendRequest renamed to defaultSendRequest
scons files changed to compile sendRequest  and cURLpp into main library
changes in test files reflecting changed filename and function name
Add scons options, that specify curl location

--curl-libpath and --curl-includepath options added
Modify readme

added information about --openssl-libpath and --openssl-includepath parameters
readme restructured, as it became too redundant
Fix service constructor comment
Merge pull request #29 from swat32exe/add-default-network

Add default sendRequest