added tooltips with user name and out/in counts
basic highlighting of in and out links on mouseover
highlight clicked node with paths and branch nodes
colour distinction for in and out links and nodes in css
colour distinction for branch nodes that have both in and out
refactored highlight classnames to use same names on all element types
added working dirs to .gitignore
moving paths, circles and texts to and from foreground works
improved colours slightly
added sidebar with lists of retweeted and retweeted by
added function to select user by name
select input for users
formatted <ul> without bullets
colour markers like paths
small formatting change