Add install script and install one-liner

Author: 0xZDH

README.md

@@ -21,6 +21,8 @@ stop     Wed 07 Oct 2020 05:00:00 AM UTC
 3. For persistence, add it to your .bashrc or similar:
     * `source "$HOME/.cmdw"`
 
+Install one-liner: `source <(curl -s https://raw.githubusercontent.com/0xZDH/cmdw/master/install.sh)`
+
 ## History Size:
 If required, the user can modify the size of the maintained history file by setting CMDWSIZE as an environment variable (Default: 3,000):
 * `export CMDWSIZE=1000`

install.sh

@@ -0,0 +1,32 @@
+#!/bin/bash
+#######################################
+# Automate the install process for .cmdw 
+# wrapper.
+#
+# Install:
+#   source <(curl -s https://raw.githubusercontent.com/0xZDH/cmdw/master/install.sh)
+#######################################
+
+# Validate the current terminal is Bash or Zsh.
+[ -n "$BASH_VERSION" -o -n "$ZSH_VERSION" ] || return 0
+
+# Download cmdw.sh to our home directory. Force the file
+# to be overwritten when it exists to allow for updates
+# to be installed.
+curl -s -o "$HOME/.cmdw" \
+  -q "https://raw.githubusercontent.com/0xZDH/cmdw/master/cmdw.sh"
+
+# Identify current shell type
+[ -n "$ZSH_VERSION" ] && \
+  shell_file="$HOME/.zshrc" || \
+  shell_file="$HOME/.bashrc"
+
+# Add .cmdw to our shell profile
+[ ! "$( grep 'source $HOME/.cmdw' "$shell_file" )" ] && \
+  echo '[ -f $HOME/.cmdw ] && source $HOME/.cmdw' >> "$shell_file"
+
+# Reload our shell profile
+source "$shell_file"
+
+# Clean up
+unset shell_file