Fixed a few minor issues in the process (typoed "square" in previous
commit")
Put curly braces around blocks that didn't have them for consistency.
Notably, re-ordered arguments for "cylinder" since the manual says if
you have named arguments, all following arguments must be named. So now
all cylinders have the height first, unnamed, followed by either r= or
d=, and then $fn= if it isn't otherwise specified in the block.
Add/remove lots of spacing for consistency. Add/remove a few parenthesis
for arithmetic readability.
Actually undo previous spacing because I disagree with the style guide
referenced previously.
