TensorBoard doesn't handle ~ in paths properly

[team Dandelion Mané]

Right now, TensorBoard does not properly evaluate a path beginning with ~ (at least on mac). Example:

(tensorflow) ~/space❯ pwd
/Users/danmane/space
(tensorflow) ~/space❯ tensorboard --logdir=~/foo/zoid --debug --host=localhost
INFO:tensorflow:TensorBoard is in debug mode.
INFO:tensorflow:Starting TensorBoard in directory /Users/danmane/space
INFO:tensorflow:TensorBoard path_to_run is: {'/Users/danmane/space/~/foo/zoid': None}