Render the git graph on the server (#12333)

Rendering the git graph on the server means that we can properly track flows and switch from the Canvas implementation to a SVG implementation.

* This implementation provides a 16 limited color selection
* The uniqued color numbers are also provided
* And there is also a monochrome version
*In addition is a hover highlight that allows users to highlight commits on the same flow.

Closes #12209

Signed-off-by: Andrew Thornton art27@cantab.net
Co-authored-by: silverwind <me@silverwind.io>

.stylelintrc

@@ -1,8 +1,5 @@
 extends: stylelint-config-standard
 
-ignoreFiles:
-  - web_src/less/vendor/**/*
-
 rules:
   at-rule-empty-line-before: null
   block-closing-brace-empty-line-before: null