Update Sketch Icon Library with new assets

[joshblack]

We've had several PRs that update the icon library assets and we need to synchronize these additions/changes with the Sketch library.

[chrisconnors-ibm]

this tranche of icons from @conradennis last PR is also on our websites but not yet surfaced in our kits: #4789

[lnajjar]

Yes, when you update the icons on the Carbon Design System Web site, will you please update the icons in the Sketch library? For example, there are Web site icons for "Undo" and "Redo" that do not appear in the Sketch library.

[chrisconnors-ibm]

Yes, when you update the icons on the Carbon Design System Web site, will you please update the icons in the Sketch library? For example, there are Web site icons for "Undo" and "Redo" that do not appear in the Sketch library.

@lnajjar are you using the correct Libraries? They're both there already.

[lnajjar]

@chrisconnors-ibm , you're right. I did not install the "IBM Icons" because I was not designing an application for IBM. Thank you for telling me where to find the icons.