Make prePadding configurable

[kutsan]

vim-devicons/plugin/webdevicons.vim

Line 719 in 82df484

let padding = g:WebDevIconsNerdTreeAfterGlyphPadding

We can configure the after padding but there is no way for pre one. I want to add a little bit more spaces before each glyph but I have to do that manually.

[ryanoasis]

Yes this is a very good idea. I think next release we will make a lot of things configurable: artifactFix, redraw, this left side padding

[kutsan]

Thanks!