Merge branch 'master' of https://github.com/Noovolari/leapp

docs/index.md

@@ -28,6 +28,20 @@ You can install Leapp by downloading the pre-built binaries for your OS [here](h
 
 Unzip the package and double-click on the executable to install.
 
+### Prerequisite for using on Linux systems
+Currently, we have `libsecret` and `gnome-keyring` as dependencies to store all sensitive data into the keyring; you **may** need to install them before running Leapp.
+Depending on your distribution, you will need to run the following command:
+
+* Debian/Ubuntu:
+    - `sudo apt-get install gnome-keyring`
+    - `sudo apt-get install libsecret-1-dev`
+* Red Hat-based:
+    - `sudo yum install gnome-keyring`
+    - `sudo yum install libsecret-devel`
+* Arch Linux:
+    - `sudo pacman -S gnome-keyring`
+    - `sudo pacman -S libsecret`
+
 ## Logs
 
 By default, Leapp writes logs to the following locations: