redmine-a1-theme v2.0.0 - compatible with Redmine 3.4

• Merge changes from 2.0.0 version of original theme.
  From original changelog:
  • Supported Redmine versions: 3.4 - 1.0
  • Redmine 3.4 fixes
  • New styles for checkbox and radio inputs
  • Multiple select2 styles
  • Margin fixes for inputs
  • Select2 styles for new CRM
  • Date field styles
  • Glyphs for moving arrows on the main menu
  • New object "+" button support
  • Tabs buttons styles
  • Gravatar fixes for Redmine 3.3
  • Responsive colors
• Fix compatibility with Redmine 3.4.
• Remove tags-related styles to not conflict with other tags plugins.
• Hide too long SVN properties in repository view.