linux code readability improvements

- Removed unneeded return statement
- Improved redebility by adding else blocs
- Renaed bufffer to char_buffer for python 2.x compatibility

Author: guiweber

readchar/readchar_linux.py

@@ -13,21 +13,22 @@
 def readchar(wait_for_char=True):
     old_settings = termios.tcgetattr(sys.stdin)
     tty.setcbreak(sys.stdin.fileno())
-    buffer = ''
+    char_buffer = ''
     try:
         if wait_for_char or select.select([sys.stdin, ], [], [], 0.0)[0]:
             char = os.read(sys.stdin.fileno(), 1)
-            buffer = char if type(char) is str else char.decode()
+            char_buffer = char if type(char) is str else char.decode()
     except Exception:
-        buffer = ''
+        char_buffer = ''
     finally:
         termios.tcsetattr(sys.stdin, termios.TCSADRAIN, old_settings)
 
     while True:
-        if buffer not in key.ESCAPE_SEQUENCES:
-            return buffer
-        c = readchar(False)
-        if c is None:
-            return buffer
-        buffer += c
-    return buffer
+        if char_buffer not in key.ESCAPE_SEQUENCES:
+            return char_buffer
+        else:
+            c = readchar(False)
+            if c is None:
+                return char_buffer
+            else:
+                char_buffer += c