Port to Maverics.

This patch depends on https://github.com/jubatus/jubatus-mpio/pull/15 and https://github.com/jubatus/jubatus-msgpack-rpc/pull/11.

The build procedure is as following:

Build jubatus_core in C++11 mode:

```
CXXFLAGS="-std=c++11" ./waf configure
./waf
./waf install
```

Build jubatus-mpio as described in https://github.com/jubatus/jubatus-mpio/pull/15.

Build jubatus-msgpack-rpc with this patch https://github.com/jubatus/jubatus-msgpack-rpc/pull/11 as following:

```
./bootstrap
CXXFLAGS="-std=c++11 -DMP_FUNCTIONAL_STANDARD -DMP_MEMORY_STANDARD -DMP_UNORDERED_MAP_STANDARD" ./configure
make
make install
```

Build jubatus as following:

```
CXXFLAGS="-std=c++11" ./waf configure
./waf
./waf install
```