Release 1.5.2

• fixed $closing variable error
• set focus to search field
• fixed #Header reference in internal links (Issue #32)
• fixed error with links to non existing files (Graph)
• fixed ampersand problem in internal links and graph (Issue #47)
• added mousehover for internal links, feature request #43
• added popup feature for internal links on mobile (setting), feature request #43
• fixed padding-right issue on mobile view
• moved some instructions to the wiki
• added light mode (in the settings)
• updated katex to 0.16.4
• fixed problem with two _ (underscorces) per line in katex context