fixes an issue with user-defined message types

this patch fixes a compile time error with some user-defined
message types; a minimal example to reproduce the error in 0.8.1 is:

typedef optional_variant<
        std::tuple<int, float>
      , std::tuple<float, int, int>
      > msg_type;

    //                                    here!
    sync_send(self, atom("msg")).then([](msg_type) {});
changed version to 0.8.2
Merged changes from 0.8.2
Record CC and CXX in config.status.

This patch also adds the CC and CXX environment variables to the config.status
command in the build directory. When invoking ./build/config.status without
this extra environment variable, one might not end up with the same build
environment as in the first build.
Merge pull request #120 from mavam/master

Record CC and CXX in config.status.