Add basic terminal color support

Also added a little command to test color support. This will come in
handy!

client.go

@@ -119,6 +119,9 @@ func (c *Client) handleShell(channel ssh.Channel) {
 		if isCmd {
 			// TODO: Factor this out.
 			switch parts[0] {
+			case "/test-colors": // Shh, this command is a secret!
+				c.Write(ColorString("32", "Lorem ipsum dolor sit amet,"))
+				c.Write("consectetur " + ColorString("31;1", "adipiscing") + " elit.")
 			case "/exit":
 				channel.Close()
 			case "/help":

colors.go

@@ -0,0 +1,24 @@
+package main
+
+import (
+    "math/rand"
+    "time"
+)
+
+const RESET string =     "\033[0m"
+const BOLD string =      "\033[1m"
+const DIM string =       "\033[2m"
+const UNDERLINE string = "\033[4m"
+const BLINK string =     "\033[5m"
+const INVERT string =    "\033[7m"
+
+var colors = []string { "31", "32", "33", "34", "35", "36", "37", "91", "92", "93", "94", "95", "96", "97" }
+
+func RandomColor() string {
+	rand.Seed(time.Now().UTC().UnixNano())
+	return colors[rand.Intn(len(colors))]
+}
+
+func ColorString(format string, msg string) string {
+	return BOLD + "\033[" + format + "m" + msg + RESET
+}