TrustyCMS v6.1.3 - SVG Uploading

[danigirl329]

• Add the ability to upload SVGs to the CMS.
• This will display the SVG in the table of assets, and act as if a jpg or similar were to be uploaded.
• This adds the active_storage_svg_sanitizer gem to strip script tags from malicious svg images.
• The sizing of the thumbnails comes from the inability to render asset variants on svg content types - so in order for them not to bleed over the 100x100 size in the asset tables, i added this.