std: add a Deque data structure

[ifreund]

This is my penance for baiting andrew into deleting the existing generic queue data structures with my talk of "too many ring buffers".

The new Reader and Writer interfaces are excellent ring buffers for many use cases, but a generic queue container type is now missing.

This new double-ended queue, known more succinctly as a deque, is implemented from scratch based on the API design lessons learned from ArrayList over the years.

The API is not yet as featureful as ArrayList, but the core functionality is in place and I will be using this in my personal projects shortly. I think it makes sense to add further functions as needed based on real-world use-cases.

[myclevorname]

This can be simplified to

    return std.math.add(usize, a, b) catch error.OutOfMemory;

[ifreund]

Not sure I agree that adding more abstraction would be simpler here

[ifreund]

Added a more comprehensive test that can also be used for fuzzing.

Also added .iterator(), .at(), .front() and .back() for a more complete starting point of this API.

[andrewrk]

give it a spin:

andy@bark ~/s/zig (master)> g DeprecatedLinearFifo src/
src/Compilation.zig:const DeprecatedLinearFifo = @import("deprecated.zig").LinearFifo;
src/Compilation.zig:]DeprecatedLinearFifo(Job),
src/Compilation.zig:c_object_work_queue: DeprecatedLinearFifo(*CObject),
src/Compilation.zig:win32_resource_work_queue: if (dev.env.supports(.win32_resource)) DeprecatedLinearFifo(*Win32Resource) else struct {

[ifreund]

Came back with fresh eyes and managed to de-obfuscate my bufferIndex() implementation without adding any expensive division or overflow :)

[ifreund]

give it a spin:

Will do!