[driver] Block device: Add missing include

[rleh]

In driver/block_device_mirror.hpp std::max() is used, but #include <algorithm> was missing.

Additionally std::min() and std::max() in the mock-up stdc++ implementation are now constexpr and a example for AVR was added (but not tested in hardware).

Furthermore BlockDevice::DeviceSize was added.

[rleh]

How the heck do we still use avr-gcc-4.9.2 for Circle CI? It was released in October 30, 2014. Gee. 😉

[salkinium]

How the heck do we still use avr-gcc-4.9.2 for Circle CI?

Because Ubuntu and most other distributions only ship the official toolchain which is stuck at gcc v5.4.0. That's okish, except it contains a compiler bug, which breaks modm CI, so now I'm building a completely new image using archlinux, which has avr-gcc v7.2.0.

[rleh]

GCC 5.4 should be fine for this PR.
But the Circle CI container is based on Ubuntu 14.04 which ships avr-gcc v4.9.2.

[salkinium]

I've given up on Arch, it didn't have zmqpp headers. I've instead just compiled avr-gcc v7.2.0 + binutils for Ubuntu 17.10 here to use in our current Ubuntu based CircleCI images.

[daniel-k]

I've given up on Arch, it didn't have zmqpp headers.

There's an AUR package for that: https://aur.archlinux.org/packages/zmqpp/

[salkinium]

There's an AUR package for that

And… there are issues with linking against system libraries. I don't feel like debugging archlinux on a docker image running in CircleCI. I mean there is a limit to my masochist tendencies.

[daniel-k]

And… there are issues with linking against system libraries.

Interesting, it's running smoothly on my system.

I don't feel like debugging archlinux on a docker image running in CircleCI. I mean there is a limit to my masochist tendencies.

However, this makes sense too 😄

[salkinium]

CircleCI is now running avr-gcc 7, but:

algorithm_base.hpp:70:2: note: 'constexpr const T& std::max(const T&, const T&) [with T = long unsigned int]' is not usable as a constexpr function because:
  max(const T& a, const T& b)
  ^

Happy debugging ^^

[rleh]

algorithm_base.hpp:76:2: error: body of constexpr function 'constexpr const T& std::max(const T&, const T&) [with T = long unsigned int]' not a return-statement

Because: CircleCI still uses avr-g++ (GCC) 4.9.2 (see ci/circleci: hosted-unittests -> Check environment)

@salkinium Could you please initiate a new CircleCI build? I rebased this branch on develop, so the updated CircleCI config file from #337 is included.