Add C++ and compiler tests to appveyor matrix
Add C++ and compiler tests to appveyor matrix

- Remove the `os` property to move to the new, faster build environment.
- Use the `check` target for C++ build to run C++ and gbc tests.
- Update boost to version 1.58.

gencer/bond,sapek/bond,chwarr/bond,alfpark/bond,chwarr/bond,sapek/bond,jdubrule/bond,alfpark/bond,jdubrule/bond,ant0nsc/bond,jdubrule/bond,Microsoft/bond,gencer/bond,Microsoft/bond,chwarr/bond,chwarr/bond,sapek/bond,jdubrule/bond,sapek/bond,upsoft/bond,tstein/bond,gencer/bond,Microsoft/bond,upsoft/bond,tstein/bond,upsoft/bond,upsoft/bond,tstein/bond,Microsoft/bond,tstein/bond,gencer/bond,sapek/bond,ant0nsc/bond,ant0nsc/bond,sapek/bond,chwarr/bond,chwarr/bond,tstein/bond,Microsoft/bond,gencer/bond,jdubrule/bond,Microsoft/bond,alfpark/bond,tstein/bond,alfpark/bond,ant0nsc/bond,jdubrule/bond