Fix missing semicolon in JS code.

Signed-off-by: Rogério Brito <rbrito@ime.usp.br>
data: readability.css: Reformat for code readability.

This was performed with the following command:

    csstidy readability.css --preserve_css=true \
            --template=low --merge_selectors=0 \
            --optimise_shorthands=0 \
            readability.new.css

There is still a lot of ancient things that should be removed (things
related to typekit, for instance).

Signed-off-by: Rogério Brito <rbrito@ime.usp.br>
data: readability.js: Fix title of the Dark mode.

Signed-off-by: Rogério Brito <rbrito@ime.usp.br>
data: resources.js: Avoid creating/leaking global variables.

Signed-off-by: Rogério Brito <rbrito@ime.usp.br>