rename readme.txt to markdown file

Changed readme.txt to readme.md to see the markdown syntax that was already there.

Author: gajrajgchouhan

Assembler/README.txt renamed to Assembler/README.md

@@ -1,5 +1,5 @@
 # Python-Assembler
-#WE NEED A FREE T-SHIRT
+#WE NEED A FREE T-SHIRT.
 This program is a simple assembler-like (intel-syntax) interpreter language. The program is written in python 2. 
 To start the program you will need to type