Added correct version string for bundle branch 2.3.x

Used version string from https://packagist.org/packages/mopa/bootstrap-bundle
Merge pull request #558 from malberts/patch-1

Added correct version string for bundle branch 2.3.x
Added bundle branch 2.3.x information.
Merge pull request #559 from malberts/patch-2

Added bundle branch 2.3.x information.
Updated datepicker to close on esc key or on blur
Update config `form.row_wrapper_class` default value to prevent a float bug

With the previous configuration, `{{ form_row(form.field) }}` (for a "horizontal" form) was generating several `col-*-*` without a `row` to wrap them around. This was causing weird layout bugs.
Add space between `widget_form_group_attr.class` and `row_wrapper_class` to avoid mangling class names
Merge pull request #562 from peterrehm/master

Updated datepicker close handling
Merge pull request #564 from lemoinem/patch-1

Update config `form.row_wrapper_class` default value to prevent a row/col bug
Added fixes