remove refs to d3 format

Author: archmoj

src/plots/cartesian/layout_attributes.js

@@ -278,7 +278,6 @@ module.exports = {
 
         pattern: {
             valType: 'enumerated',
-            // TODO could add '%H:%M:%S'
             values: ['day of week', 'hour', ''],
             dflt: '',
             role: 'info',
@@ -287,8 +286,6 @@ module.exports = {
                 'Determines a pattern on the time line that generates breaks.',
                 'If *day of week* - Sunday-based weekday as a decimal number [0, 6].',
                 'If *hour* - hour (24-hour clock) as a decimal number [0, 23].',
-                '*day of week* and *hour* are similar to *%w* and *%H* directives',
-                'applied in `tickformat`, see https://github.com/d3/d3-time-format#locale_format',
                 'for more info.',
                 'Examples:',
                 '- { pattern: \'day of week\', bounds: [6, 0] }',