Added installation on arch linux. (#103)

README.md

@@ -39,6 +39,15 @@ For other architectures, please search for `vnote` at [software.opensuse.org](ht
 
 We don't support Leap 42 and below due to the Qt version. Please use AppImage or build it yourself.
 
+### Arch Linux
+VNote on Arch Linux can be installed from the AUR as [vnote-git](https://aur.archlinux.org/packages/vnote-git/)
+
+```shell
+git clone https://aur.archlinux.org/vnote-git.git
+cd vnote-git
+makepkg -sic
+```
+
 ## MacOS
 [![Build Status](https://travis-ci.org/tamlok/vnote.svg?branch=master)](https://travis-ci.org/tamlok/vnote)