ASCII-8BIT characters cause errors when using Uglifier

commit 1: addresses Uglifier error
commit 2: addresses items no longer being fluid

# 1:

When using Uglifier to compress the code for example in an asset pipeline the following error occurs `Uglifier - "\xE2" from ASCII-8BIT to UTF-8`.

This is due to the usage of the left/right arrows characters and the dots in the comment next to the dots option and the file is encoded as ASCII-8BIT.

This can be fixed by removing the dots from the comment string and using html entities for the arrows instead.

IMO using html entities for the arrows is the safer anyway. NB: the dot characters in the comment also caused the error which is why I just replaced it with the word "dots"

# 2:
The older code in the download file on your site sets the items to be fluid. For some reason this was changed to pixels.

Even with the option `fluid: true` i found loading a page and then resizing bigger would show part of the next slide.

This fix checks if `fluid: true` and if so uses the percentage method like the older code on the site, with this in place it works as I expected.