Made the installation section of the readme a bit more robust

README.md

@@ -10,23 +10,36 @@ sudo cp /tmp/scantopdf/scantopdf /usr/local/bin/scantopdf
 sudo chmod 755 /usr/local/bin/scantopdf
 ```
 
+Please verify that the path `/usr/local/bin` is in the global variable `$PATH`.
+To verify this, issue the following command:
+```bash
+echo "$PATH" | grep "/usr/local/bin"
+```
+if there is a line of output, you are all good!
+If there isn't, then issue the following command:
+```bash
+export PATH="/usr/local/bin:$PATH"
+echo "export PATH=\"/usr/local/bin:\$PATH\"" | sudo tee -a /etc/profile
+```
+
+
 ## Usage
 
 To use this script, follow this steps
 1. Open a terminal
 2. Go the location of the file you want to "convert" with the following command
-    ```
+    ```bash
     cd <path>
     ```
     where `<path>` is the location of the **folder** where lies the file to convert.
 3. Use the command `scantopdf` and give it, as an argument, the file you want to
     convert. If the file name contains **spaces**, surround it with **quotes** `"`
-    ```
+    ```bash
     scantopdf "I Promessi Sposi.pdf"
     ```
     Optionally you can give it the `-v` flag (before the name of the file), to make
     the script verbose, so instead of doing its job without saying anything, it will
     print each step that it's doing.
-    ```
+    ```bash
     scantopdf -v "La Divina Commedia.pdf"
     ```