Use print.css when printing

After the print stylesheet was added in 0111c5f it was being included
with the stylesheet_link_tag helper as print.css. The helper then
thought this was at the route and was including it as /print.css at the
root of the domain. This commit removes the .css which allows the helper
to function correctly.
Move manuals sections into _hmrc_sections

As part of trying to separate out manuals, move the hmrc specific parts into their own file.

HMRC manuals are going to have a different design to other manuals so will use different templates. Seperating them will make the code easier to read as it won't be doing strange seeming things to account for the different data structures that HMRC's manuals and our own manuals exist in.
Merge pull request #90 from alphagov/use-print-css-correctly

Use print.css when printing
Remove HRMC Javascript

Simplify the JS by removing the edge case handling for HRMC manuals (which no longer need it)
Precompile print.css in Production

As print.css isn't precompiled by default, it needs added to the list of
stylesheets to compile in the Production environment.
Merge pull request #91 from alphagov/precompile-print-css

Precompile print.css in Production
Remove CSS only used for HMRC manuals

I'm trying to restructure this CSS a bit to be less complicated, as part of that I'm removing HMRC-only styles which will be sorted out when the next iteration of HMRC manuals is complete
remove div that's not required
Unify styles between index and show pages

Show and Index have a lot in common above the main body content (they both have a Summary and an optional Body which should be two-thirds width at max screen size)

This commit removes some divs that weren't necessary, and shares styles between these parts of the page so there is less duplication of css.

This commit renames 'manual-section' to 'manual-body' which seems like a more understandable name.

This commit also refactors the index page into a list of sections rather than a lot of stacked headers (which it was before because it had to accommodate different depths of content, so some would be links to other pages and some would have copy underneath them which folded out when you clicked the header - yuck.)
Remove styles only used for HMRC

The presentation of HMRC manuals is changing, so remove hmrc specific styles for now so can refactor this css into a more logical file for supporting one type of manual, to which we can later add support for a different layout

Remove headerless section handling which is overcomplicated for what we need, replace with some css to make paragraphs above h2s two-thirds width.
Remove styling from remaining hmrc manuals

The leftover markup for HMRC manuals is being picked up by the collapsible styles and javascript, so strip those classes from the markup so the hmrc manuals will be displayed painly without broken styling
Use semantic values for colours not $grey and $black

Good catch @edds, I had forgotten about these variables.
Removed duplication between hmrc templates
Add js to auto open sections

In Specialist publisher we offer instruction for how to link to a paragraph elsewhere in the page or on another page. This functionality works using anchors. Make sure if a link is clicked going to a paragraph elsewhere on the page, that the containing section is opened.
Merge pull request #92 from alphagov/remove-hmrc-manuals-collapsible-support

Remove hmrc manuals collapsible support
Merge pull request #93 from alphagov/make-linking-to-sections-work

Add js to auto open sections
Make all of list item clickable

This commit pushes the whitespace into the padding of the link tag so that the whole of the link area is clickable rather than just the two-thirds with text in.
Merge pull request #94 from alphagov/make-clicking-work-again

Make all of list item clickable