Prevent repl tests from hanging if homedir() is a symlink

I am testing julia on a machine where my home directory is a
symlink.  Unfortunately, this means the repl tests hang, as they
wait for the homedir to be given at the shell prompt, but instead
the pwd() is printed.  `pwd()` calls `uv_cwd()` which calls
`getcwd()`, which [will always resolve symbolic links](https://stackoverflow.com/a/1545838/1558890),
thus printing something other than `homedir()` on my system.
This changes the repl tests to wait for `realpath(homedir())`
instead of `homedir()`.

test/repl.jl

@@ -86,10 +86,10 @@ if !is_windows() || Sys.windows_version() >= Sys.WINDOWS_VISTA_VER
  write(stdin_write, ";")
  readuntil(stdout_read, "shell> ")
  write(stdin_write, "cd\n")
- readuntil(stdout_read, homedir()[max(1,end-39):end])
+ readuntil(stdout_read, realpath(homedir())[max(1,end-39):end])
  readuntil(stdout_read, "\n")
  readuntil(stdout_read, "\n")
- @test pwd() == homedir()
+ @test pwd() == realpath(homedir())
  end
  cd(origpwd)