add iOS and versions to Safari percent rounding warning; fixes #10723
Better documentation and optimized examples for grid classes
Added abridged form of 'What's included' docs to README
Moved 'getting started' link out of 'What's included' section in README
Apply help-block class to help text in customize.html
Remove .ruby-version due to https://github.com/twbs/bootstrap/commit/4f20a29c329aa58919919426cbd2190fabfdb723
Remove "Remove margin on the body" from base css docs

Normalize did that.
also use .col-sm-* in other .form-horizontal example for consistency
use .col-xs-* in "Forms: Column Sizing" docs so more responsive
table contextual classes docs: .col-lg-* => .col-xs-*
Merge pull request #10888 from twbs/favor-xs-in-docs

use .col-xs-* in "Forms: Column Sizing" docs so more responsive
Merge pull request #10889 from twbs/contextual-table-docs-xs

table contextual classes docs: .col-lg-* => .col-xs-*
Merge pull request #10883 from ZDroid/patch-3

Remove "Remove margin on the body" from base css docs
Merge pull request #10865 from Quy/master

Apply help-block class to help text in customize.html
Merge pull request #10856 from akalicki/grid_class_docs

Better documentation and optimized examples for grid classes
Merge pull request #10864 from akalicki/included_files

Added abridged form of 'What's included' docs to README
document that multiple navbars aren't supported by default; addresses #10824
add maintenance note regarding #10864's addition
Merge pull request #10826 from twbs/doc-multiple-navbars-unsupported

document that multiple navbars aren't supported by default
Merge pull request #10806 from twbs/ios-safari-pct-rounding

add iOS and versions to Safari percent rounding warning; fixes #10723