Update the readme with the new parameter

README.md

@@ -12,9 +12,19 @@ On RedHat/CentOS, you may need to have EPEL installed before running this role.
 
 Available variables are listed below, along with default values (see `defaults/main.yml`):
 
+The name of the packge to install to get `pip` on the system.
+
+    pip_package_name: python-pip
+
+For example:
+
+    pip_package_name: python3-pip
+
+A list of packages to install with pip.
+
     pip_install_packages: []
 
-A list of packages to install with pip. Examples below:
+Examples below:
 
     pip_install_packages:
       # Specify names and versions.
@@ -22,19 +32,19 @@ A list of packages to install with pip. Examples below:
         version: "1.2.3"
       - name: awscli
         version: "1.11.91"
-    
+
       # Or specify bare packages to get the latest release.
       - docker
       - awscli
-    
+
       # Or uninstall a package.
       - name: docker
         state: absent
-    
+
       # Or update a package ot the latest version.
       - name: docker
         state: latest
-    
+
       # Or force a reinstall.
       - name: docker
         state: forcereinstall