Some initial work on new site for 1.0

Clean up everything that was there, create site skeleton using bootstrap and plain HTML.
Add direct download links for current version of packages
experiment with menu
Improve doc and workflow images; and tweak index css.
Add menus to every page, fix support glyph and add jquery for bootstrap.
Add site banner, fix up page title, and adjust menu position
Jekyll-ify site
Fix images for download page caused by move to Jekyll
Redo main page in line with feedback received.  Separate download and develop pages
Remove index direct download
Draft generic Sanger terms and conditions
Point developers to organisation github not samtools.
Add link anchors
Update list of publications based on feedback from Petr. Add BCFtools manual
Merge branch 'master' into 1.0_site
Replace front page with coming soon
Add Thomas's blurb
add {{ site.baseurl }} to links on index
Preliminary workflow for WGS/WES
Update workflow based on feedback and fix header links when JS off

Add variant filtration and evaluation example.
Fix some errors in the grammar of the workflow text.
Remove .html from links in menu.