Upgrade Bootil to new C++ standard(s)

[neico]

As C++17 (C++1z) is getting closer I thought maybe it's time to get at least up to C++11 and C++14 standards...

Doing so not only reduces platform specific code, it also reduces dependencies and therefore should make the end result smaller and faster, not to mention compiler optimisations.

One example is C++11's thread class, so far the only thing I missed on that would be setting a thread name, which is rather easy to deliver trough std::thread::native_handle() (not that Bootil supported that in the first place)

Another example would be the filesystem TS (based on boost's one) that "most modern" compilers include:
GCC/G++
MSVC/VC++

Note: It seems that clang hasn't started on the TS yet (much to my surprise, one could include the boost fs lib for this case): http://libcxx.llvm.org/ts1z_status.html

I guess the first step would be to identify places that can be improved using the new standards (ex. Bootil/Threads) and create a TaskList in here

[Bo98]

What was stopping it before was actually GMod (don't know about Rust). It shouldn't really be an issue enabling C++11/C++14 though since it's backwards compatibile with existing code.