Rename demo.sh scripts to try.sh

This is because they are under the try section. I'm aware that there's a
script called try.me.sh but that's not been decided on a name change. It
probably should be changed to try.sh to be consistent and probably will
be but it's not been yet.

The manifest files in tmp/ have been updated as well, including the
macOS Numbers file.

2013/birken/README.md

@@ -44,7 +44,7 @@ make clobber CDEFINE=-DZ=7500 alt
 
 perl -e 'map{map{print int(rand()*8);}(0..16);print chr(10);}(0..30);' | tr '[0-4]' ' '| ./birken.alt
 
-./demo.sh
+./try.sh
 ```
 
 If you wish to speed it up 200% you can use instead `-DZ=3750`. Doing this
@@ -65,7 +65,7 @@ Use `birken` as you would `birken.alt` above. To use the demo script with the
 original code, try:
 
 ```sh
-BIRKEN=birken ./demo.sh
+BIRKEN=birken ./try.sh
 ```
 
 PLEASE be careful if you are sensitive to flashing colours!

2013/misaka/README.md

@@ -46,7 +46,7 @@ seq -f '%.0f  ' 45 | ./horizontal_cat - misaka.c
 Alternately you can just try:
 
 ```sh
-./demo.sh
+./try.sh
 ```
 
 NOTE: Use - for standard input.  For example: