Add an install message

To help people who may think the package doesn't work

Author: michaelblyons

messages.json

@@ -1,4 +1,5 @@
 {
+    "install": "messages/install.md",
     "7.0.0": "messages/7.0.0.md",
     "6.0.0": "messages/6.0.0.md",
     "5.0.0": "messages/5.0.0.md",

messages/install.md

@@ -0,0 +1,20 @@
+⚠ Important Note ⚠
+
+Due to a Sublime Text limitation on file
+extensions, highlighting for SSH Config
+files is NOT ACTIVATED AUTOMATICALLY for
+~/.ssh/config, where it is most useful.
+
+The easiest way to adjust is to open your
+SSH Config file from the command palette
+(Primary+Shift+P) and use the following
+command:
+
+    SSH Config: Open SSH Config File
+
+For more details (and more workarounds),
+see the wiki page at:
+
+https://github.com/robballou/sublimetext-sshconfig/wiki/Activate-SSH-Config-highlighting
+
+⚠ Important Note ⚠