Updated conky and zsh

  * (manual) zsh/zshrc: changed inclusion path, instead of explicit path
    use shell variable;
  * (manual) conky/read-tip.lua: use '~/.conky' for conf files;
             conky/tip-files.lua: made string concat more fancy;

Signed-off-by: Vladimir Lomov <lomov.vl@gmail.com>