Initial adding of snow.html
Move the html variable
Extract method
Eliminate unused variable
Snowflakes per pixel per second divided by assumed fbs is a constant value.

```delta``` is a bad name but we'll have to keep it for now. 
The html variable is only needed in the resize function
Don't delay the resize
Extract a poll object
Move guard condition in a method
Move a variable near to its first use
Extract Scene object