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.

1998/banks/README.md

@@ -69,7 +69,7 @@ See the author's remarks in [scenery](#scenery) for more details on the scenery
 files.
 
 
-### Try:
+## Try:
 
 For a fun time after running the above command, hold down the up arrow and left
 arrow for about 10 seconds and see what happens. Or, if you wish to really use

1998/bas2/README.md

@@ -13,7 +13,7 @@ echo text | ./bas2
 ```
 
 
-### Try:
+## Try:
 
 ```sh
 ./try.sh

1998/dlowe/README.md

@@ -26,7 +26,7 @@ STATUS: missing or dead link - please provide them
 For more detailed information see [1998 dlowe in bugs.md](/bugs.md#1998-dlowe).
 
 
-### Try:
+## Try:
 
 ```sh
 ./dlowe < README.md

1998/dorssel/README.md

@@ -15,7 +15,7 @@ echo text | ./dorssel
 ```
 
 
-### Try:
+## Try:
 
 ```sh
 ./try.sh

1998/fanf/README.md

@@ -15,7 +15,7 @@ this entry because of the system resources it requires.
 ```
 
 
-### Try:
+## Try:
 
 Enter an expression on standard input.  To try some we have selected:
 

1998/schnitzi/README.md

@@ -30,7 +30,7 @@ echo x y z | ./sort
 where `n` and `x`, `y` and `z` are numbers.
 
 
-### Try:
+## Try:
 
 ```sh
 ./try.sh

1998/schweikh2/README.md

@@ -18,7 +18,7 @@ or
 ```
 
 
-### Try:
+## Try:
 
 ```sh
 ./yarng 5

1998/schweikh3/README.md

@@ -30,7 +30,7 @@ find dir -type f -print | ./samefile
 Maybe you will not need to buy another 10 GB disk to store them.  :-)
 
 
-### Try:
+## Try:
 
 If you're in this winning entry's directory:
 

1998/tomtorfs/README.md

@@ -23,7 +23,7 @@ xor       : value to xor the final CRC with (hexadecimal)
 ```
 
 
-### Try:
+## Try:
 
 ```sh
 ./try.sh