Fix heading level of 'Try' section

It was agreed to be '## Try:' but there were many files where it was
'### Try:'. This has been corrected.

1988/applin/README.md

@@ -10,7 +10,7 @@ the source of the alt code), of [applin.c](applin.c), can be found in
 program.  See the [Alternate code](#alternate-code) section below for details.
 
 
-### Try:
+## Try:
 
 ```sh
 ./applin

1988/dale/README.md

@@ -16,7 +16,7 @@ STATUS: INABIAF - please **DO NOT** fix
 For more detailed information see [1988 dale in bugs.md](/bugs.md#1988-dale).
 
 
-### Try:
+## Try:
 
 ```sh
 ./try.sh

1988/litmaath/README.md

@@ -15,7 +15,7 @@ There is an alternate version provided. See the [Alternate
 code](#alternate-code) section below.
 
 
-### Try:
+## Try:
 
 ```sh
 ./litmaath eschew obfuscation

1988/reddy/README.md

@@ -5,7 +5,7 @@ make all
 ```
 
 
-### Try:
+## Try:
 
 ```sh
 ./reddy

1988/robison/README.md

@@ -5,7 +5,7 @@ make all
 ```
 
 
-### Try:
+## Try:
 
 ```sh
 ./robison 80 10

1988/westley/README.md

@@ -9,7 +9,7 @@ code](#alternate-code) section below for how to use the original and why one
 might wish to do so.
 
 
-### Try:
+## Try:
 
 ```sh
 ./westley