inkview: add page (#2736)

pages/common/inkview.md

@@ -0,0 +1,12 @@
+# inkview
+
+> Inkscape graphical SVG previewer.
+> Also functions as a slideshow viewer.
+
+- Preview an SVG:
+
+`inkview {{path/to/file.svg}}`
+
+- Preview multiple SVGs (use arrow keys to navigate):
+
+`inkview {{path/to/file_a.svg}} {{path/to/file_b.svg}} {{path/to/file_c.svg}}`