Merge pull request #158 from mortonfox/no-window-new-tab

Handle situation where iTerm is running but has no windows.

@mortonfox Thanks! I really like ```set curTerm to (current terminal)``` 
I'm going to merge the pull request but this got me thinking about the iTerm conditions we are handling.

1. iTerm is not open
2. iTerm app is running but no iTerm windows are open
3. iTerm app is running and we have iTerm windows open. 

I'm not handling #2 correctly.  

I'm going to completely rewrite this to verbosely handle all events. This will make the code easier to read and correctly handle what is going on.   

Thanks for taking the time to contribute.

Author: Matt Turner

Shuttle/apple-scpt/iTerm-stable-new-tab-default.scpt

@@ -16,7 +16,13 @@ end scriptRun
 on CommandRun(withCmd, withTheme, theTitle)
 	tell application "iTerm"
 		if it is running then
-			tell the current terminal
+			set curTerm to (current terminal)
+			try
+				set tmp to curTerm
+			on error
+				set curTerm to (make new terminal)
+			end try
+			tell curTerm
 				set newSession to (launch session withTheme)
 				tell the last session
 					reopen
@@ -41,4 +47,4 @@ on CommandRun(withCmd, withTheme, theTitle)
 			end tell
 		end if
 	end tell
-end CommandRun
+end CommandRun