check for OSX terminal env variables.

lib/program.js

@@ -68,6 +68,12 @@ function Program(options) {
     || process.env.TERM
     || (process.platform === 'win32' ? 'windows-ansi' : 'xterm');
 
+  // OSX
+  this.isOSXTerm = process.env.TERM_PROGRAM === 'Apple_Terminal';
+  this.isiTerm2 = process.env.TERM_PROGRAM === 'iTerm.app'
+    || !!process.env.ITERM_SESSION_ID;
+
+  // VTE
   // NOTE: lxterminal does not provide an env variable to check for.
   // NOTE: gnome-terminal and sakura use a later version of VTE
   // which provides VTE_VERSION as well as supports SGR events.