Issue #2142653 by corbacho, sqndr, LewisNyman, floretan, BarisW, G-raph, JamesLefrère, lokapujya, LoMo, Outi: Change default logo filetype to .svg and add an SVG version of Druplicon

Issue #1903048 by DickJohnson, emma.maria, lauriii, mbrett5062, JamesLefrère, lilGemVinny: Revise Bartik template indentation inline with best practices

Issue #1663166 by LewisNyman, Manuel Garcia, JamesLefrère, BarisW, sqndr, tompagabor: Clean up system admin css

Issue #2278415 by G-raph, Upchuk, Karmen, JamesLefrère, herom | emma.maria: Fixed Bartik dropbutton styling looks bad.

Issue #2152521 by prashantgoel, LewisNyman, sghoweri, mrjmd, LoMo, JamesLefrère, Manjit.Singh: Fixed User login page looks cramped on mobile.

Issue #1972122 by akalata, mortendk, JamesLefrère, pakmanlh, ckrina, sun: Remove the DIV tag around block content.

Issue #2033211 by jwilson3, LewisNyman, sqndr, tim.plunkett, JamesLefrère | yannickoo: Move Seven CSS files into css directory.

Revert "Issue #2033211 by LewisNyman, tim.plunkett, JamesLefrère | yannickoo: Move Seven CSS files into css directory."

This reverts commit 16e60c42.

Issue #2033211 by LewisNyman, tim.plunkett, JamesLefrère | yannickoo: Move Seven CSS files into css directory.