gitweb: Show target of symbolic link in "tree" view

gitweb: Show target of symbolic link in "tree" view

In "tree" view (git_print_tree_entry subroutine), for entries which are
symbolic links, add " -> link_target" after file name (a la "ls -l").

Link target is _not_ hyperlinked.

While at it, correct whitespaces (tabs are for aling, spaces are for indent)
in modified git_print_tree_entry subroutine.

Signed-off-by: Jakub Narebski <redacted>
Signed-off-by: Junio C Hamano <redacted>