[gnome-devel-docs] demos: Clarify what your_username comes from.

[David King <davidk src gnome org>]

commit 3ad88f176d6ac39732af345a28dbafb6dd899bb3
Author: Sebastian Rasmussen <sebras gmail com>
Date:   Sat Feb 2 03:47:13 2019 +0100

    demos: Clarify what your_username comes from.
    
    Also clarify where the commands are supposed to be entered.

 platform-demos/C/samples/hello-in-js/README | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)
---
diff --git a/platform-demos/C/samples/hello-in-js/README b/platform-demos/C/samples/hello-in-js/README
index d3ec4f4e..fcfe1c02 100644
--- a/platform-demos/C/samples/hello-in-js/README
+++ b/platform-demos/C/samples/hello-in-js/README
@@ -1,10 +1,12 @@
-To build and install this program:
+To build and install this program, run these commands from a terminal:
 
-./autogen.sh --prefix=/home/your_username/.local
+./autogen.sh --prefix=/home/$USER/.local
 make install
 
 -------------
-Running the first line above creates the following files:
+When running the first command $USER will be replaced by your username.
+
+Running the first command above creates the following files:
 
 aclocal.m4
 autom4te.cache