Mass fixes to headers in README.md files

There were many many README.md files with the wrong heading level for
different sections. These have been changed.

To help go through the changes it should be noted I used sgit and also
here is what is changed:

The 'Try', 'To build' and 'To run' lines have two '#'s. Some had one and
others had three.

An exception is that in 1984/anonymous/README.md for the alternative
code that had three '#'s. This is not consistent yet and it might be
that only two are desired. But for now that one at least has three.

2014/birken/README.md

@@ -7,13 +7,13 @@
     Alexander Prishchepov  
     <https://github.com/sans17/>  
 
-# To build:
+## To build:
 
 ```sh
 make
 ```
 
-### To run:
+## To run:
 
 ```sh
 ./prog < some_secret_or_something
@@ -21,7 +21,7 @@ make
 ./prog http://host[:port]
 ```
 
-### Try:
+## Try:
 
 ```sh
 ./prog
@@ -47,7 +47,7 @@ obfuscation awaits the reader of the source!
 
 When launched in web server mode, this application appears to deliver nothing more than a static HTML page.  But, in actuality, it provides covert file transfer over the Internet.  This is demonstrated by starting the application as a client-side downloader.  The hidden transmitted data cannot be reconstructed or even detected from the binary content of the traffic between the client and the server.
 
-### To run web server
+## To run web server
 
 ```sh
 ./prog < secret_file_to_be_downloaded
@@ -59,7 +59,7 @@ Try using the program's source code as the secret file:
 ./prog < prog.c
 ```
 
-### To run client-side downloader
+## To run client-side downloader
 
 ```sh
 ./prog http://host[:port]