Format keywords consistently in ad requests

Should now be consistent in calls to OAS and DFP for standard ads and video ads.
correct oas ad handling
Attach adserver tracking to Books.

This uses the new {@Adlink} macro that Grant made.
Merge pull request #3729 from guardian/inline-dfp-ads

Correct mobile-sized oas/dfp ads
Merge pull request #3730 from guardian/reattachOasToken

Attach adserver tracking to Books.
Merge pull request #3727 from guardian/kc-dfp-keywords

Format keywords consistently in ad requests
Fix broken build
Replace characters prohibited by DFP

In target values.
styling of dsp ads
Merge pull request #3731 from guardian/kc-dfp-kw-escape

Replace characters prohibited by DFP
give mobile-specific ad slot an different id
Merge pull request #3732 from guardian/fronts-ads-styling

Styling of DFP ads
Merge branch 'master' of github.com:guardian/frontend into memcached