Change all occurrences of "@." into "@".

"@.property" does not appear on the CoffeeScript main page unlike
"@property". Both produce the same JavaScript but my syntax highlighting
works only for the latter. ;)
Remove unnecessary whitespace.

Remove whitespace from the ends of lines. Also remove empty lines from
the beginnings and ends of files.
Unify indentation to 4 spaces in tests/.
Unify indentation to 4 spaces in src/.

Even though the original leaflet.awesome-markers.js uses an indentation
of 2 spaces, it clashes with the indentation style of the other files.