Put lines in a div & code lines in a span, Add WrapLongLines Option

[CIAvash]

This pull request:

• Puts code lines in a span: <span class="cl">...</span>
• Puts line numbers and code lines in a div: <div class="line"><span class="ln">...</span><span class="cl">...</span></div>
• Adds a WrapLongLines option for wrapping long lines
• Adds a PreWrapper type for main .chroma class, Changes Background class to bg
• Fixes Wrap code lines in spans; style default line numbers using CSS :before #549
• Fixes LineHighlight not working properly with horizontal overflow #558

I don't know if tables are needed now, unless they serve a purpose I'm not aware of.

[alecthomas]

Nice, have you visually verified that it renders correctly? If not don't worry about it, I'll clone the branch and push it up to the playground so we can mess around.

[alecthomas]

I pushed it up, looks good to me. Might be worth taking a look @bep , as this will effect Hugo's output.

[CIAvash]

Nice, have you visually verified that it renders correctly? If not don't worry about it, I'll clone the branch and push it up to the playground so we can mess around.

Yes, of course, but I haven't tested it in all browsers. Although most of them are chromium-based now, except Firefox and Safari.

Also there might be scenarios that I'm not aware of, so it's better if other people test it as well.

[alecthomas]

LGTM, @bep can take a look asynchronously and we can iterate on any issues later.