udate executable names per OS in readme

Author: nomadicGopher

README.md

@@ -1,5 +1,7 @@
 ## Instructions
 1. Download your OS's version of the program from [Releases](https://github.com/nomadicGopher/TypeScript_to_JavaScript/releases).
+    * **TypeScript_to_JavaScript.exe**: Windows
+    * **TypeScript_to_JavaScript**: Linux
 2. Add a scripts.ts file in the same directory, or remember to set the -file command-line-argument if it is outside the program's directory.
 3. Run the program with the following potential flags: `typescript2javascript.exe -minify -stream=#.##`