Updated CONTRIBUTING.md
Updated CONTRIBUTING.ru.md
Update README for flexbox compatibility
Add browsers support
Fix
Fix browsers support
Update russian README
Updated grid.ru.md
Updated grid.en.md
Updated CONTRIBUTING.md
Updated README.md
Updated README.md
Updated README.ru.md
Use flexbox version by default
update links in README
refactor mantle block

add mantle examples

Add mantle to EN README

Add mantle to RU README
Merge branch 'master' into gh-pages
add examples for mantle block