Moved around some functions definitions between files.
This commit contains some fixups to the move of the `Framework`
implementation code to a separate file in the previous commit.
* Change `Framework::send()` to use an out-of-class definition.
* Move back trivial functions back to the header file.
* Move private constructor to the top of the file in `framework.cpp`.
Replaced `<stout/windows/os.hpp>` with `<stout/os.hpp>` in stout.
The intent is that `os.hpp` includes the correct OS-specific header,
`windows/os.hpp` or `posix/os.hpp`, automatically. They should never
be included manually.
Added port mapping and network ports isolators sources to CMake.
This adds the relevant options and source files, but with a fatal
message if they're used, as we do not yet check for their
dependencies. This also adds the `mesos-network-helper` executable as
used by the port mapping isolator.
This patch adds stubs for the Python executor and scheduler, adds
support for `mesos-resolve`, adds conditional support for the old
`mesos-cli` when `ENABLE_NEW_CLI` is not set and not on Windows, and
fixes some ordering oddities.
