jgthms/bulma

#1884 New $navbar-burger-color variable
#1679 Add breakpoint based column gaps
#1905 Fix modal for IE11 #1902
#1919 New is-arrowless class for navbar items
#1949 New is-fullheight-with-navbar class for heros
#1764 New .is-sr-only helper
#2109 Add and use $navbar-breakpoint variable
New variables $control-height, $control-line-height, $pagination-min-width, $input-height
#1720 Add list element feature
#2123 Add .content ol types: .is-lower-roman, .is-upper-roman, .is-lower-alpha, .is-upper-alpha, and support for the type= HTML attribute

#1964 Allow .notification to have a .dropdown-item
#1999 Change $border to $grey-lighter in mixins
#2085 .media-content will allow scrolling horizontally if the content is too wide
#1744 Fix #1710 by using $table-striped-row-even-hover-background-color only for even rows
#2074 Allow <button> as .dropdown-item

#1749 Fix icons floating out of input area
#1993 Fixes #1992 Prevent disabled form elements hover state from overlapping, if control has add-ons elements
#1909 Fix Modal card in IE11
#1908 Fix IE11 when textarea doesn't listen to size=""
Fix #1991 The last button in list of full-width buttons has longer width
#1982 Fix navbar-burger color when color modifier is used
#1819 Fix #1137 error message for required file
Fix #1904 and #1969: hide native file input in Chrome
#2059 Remove unnecessary right margin from last level-item (level.is-mobile)