Spacing using inset and outset

[harm-smits]

Is your feature request related to a problem? Please describe.
We should consider adding spacing control in some from. A good example of this could be space-inset and space-outset. These could have numbered classes for incremental padding around the object by means of padding.

Describe the solution you'd like
A solution could look like this. Not sure whether I should add them for breakpoints though:

@for $i from 1 through 4 {
  .mesh-space--inset-#{$i} {
    padding: ($i * .4) + rem;
  }
  .mesh-space--outset-#{$i} {
    margin: ($i * -.4) + rem;
  }
}