Add 3 online compilers found on isocpp

The following three online compilers I found on https://isocpp.org/get-started is added:
Rextester
Rise4Fun
Wandbox
Add MongoDB C++ Driver

C++ Driver for MongoDB.
Add license for MongoDB C++ Driver
Add MongoDB C Driver and Libbson
Merge pull request #59 from myd7349/master

Add 3 online compilers: Rextester, Rise4Fun and Wandbox