Improve usage and installation instructions

README.md

@@ -12,6 +12,29 @@ particular, HTTP response codes are ignored (see #1).
 
     git clone https://git.kj7rrv.com/kj7rrv/netrun
     cd netrun
-    pip3 install -r requirements.txt
+    python3 -m pip install requests # Or install requests with your distro's
+                                    # package manager; just don't use pip as
+                                    # root or with sudo
     python3 netrun.py https://git.kj7rrv.com/kj7rrv/netrun/raw/branch/master/demos/shell.sh
     python3 netrun.py --interpreter=python3 https://git.kj7rrv.com/kj7rrv/netrun/raw/branch/master/demos/python.py
+    python3 netrun.py --help
+
+## Installation
+
+### Single user
+
+    # requests must be installed either with pip (run as the same user that is
+    # installing and will use netrun), or with your distro's package manager;
+    # do not run pip as root or with sudo
+    cp netrun.py ~/.local/bin/netrun
+    chmod +x ~/.local/bin/netrun
+    netrun https://git.kj7rrv.com/kj7rrv/netrun/raw/branch/master/demos/shell.sh
+
+### System-wide
+
+    # Install requests using your distro's package manager first; using pip as
+    # a regular user only installs it for that user, and using it as root/with
+    # sudo is not recommended
+    sudo cp netrun.py /usr/bin/netrun
+    sudo chmod +x /usr/bin/netrun 
+    sudo netrun https://git.kj7rrv.com/kj7rrv/netrun/raw/branch/master/demos/shell.sh