Add C++17 Structured Bindings Support for r,g,b,a and s,t,p,q Member Vectors and Mat and Quat

[ZXShady]

This PR introduces structured bindings support for improved readability and allows for more concise code
Key Changes:
- You are now allowed to use structured bindings even when GLM_FORCE_MEMBERS_XYZW macro is not defined fixing an inconsistency.
- You can use structured bindings on mat and qua types

// Before
auto w  = obj.getSize().x; 
auto h = obj.getSize().y; // calls getSize again.

// After
auto [w, h] = obj.getSize();

glm::vec3 v;
auto [x,y,z] = v; // used to be an error unless GLM_FORCE_MEMBERS_XYZW was defined

Structured bindings make the code more readable, especially when accessing multiple members of an temporary from a function call. It reduces verbosity.

No idea how to run Github C.I. on external repositories

[ZXShady]

A minor benefit to this is that it allows the classes to be reflectable by structured bindings tricks which is little bit neat.

[Groovounet]

C.I. is running here: #1340 as I didn't find another way.