Add legacy document-new/open/edit icon

Some applications might use the (I guess) legacy names for the symbolic
icons document-new, document-open, document-edit. In yaru those files
are named document-new-symbolic, document-open-symbolic,
document-edit-symbolic (which is the new name convention)
and the application (see keepassxc) might not find them.

Adding new symlinks in symbolic/actions.list for fixing it

closes #1294

icons/Suru/scalable/actions/document-new.svg

@@ -0,0 +1 @@
+document-new-symbolic.svg

icons/Suru/scalable/actions/document-open.svg

@@ -0,0 +1 @@
+document-open-symbolic.svg

icons/Suru/scalable/actions/document-save.svg

@@ -0,0 +1 @@
+document-save-symbolic.svg

icons/src/symlinks/symbolic/actions.list

@@ -39,3 +39,6 @@ selection-end-symbolic.svg selection-start-symbolic-rtl.svg
 selection-start-symbolic.svg selection-end-symbolic-rtl.svg
 system-restart-symbolic.svg system-reboot-symbolic.svg
 window-pop-out-symbolic.svg detach-symbolic.svg
+document-new-symbolic.svg document-new.svg
+document-open-symbolic.svg document-open.svg
+document-save-symbolic.svg document-save.svg