Time deltas not being displayed properly

[vlizanae]

Environment

• Operating System: linux
• Python Version: 3.5.6
• How did you install Qgrid: conda
• Python packages:

anaconda                  custom           py35h104c396_0  
anaconda-client           1.7.2                    py35_0  
anaconda-navigator        1.9.2                    py35_0  
anaconda-project          0.8.2                    py35_0  
conda-verify              3.1.0                    py35_0  
ipykernel                 4.10.0                   py35_0  
ipython                   6.5.0                    py35_0  
ipython_genutils          0.2.0            py35hc9e07d0_0  
ipywidgets                7.4.1                    py35_0  
jupyter                   1.0.0                    py35_7  
jupyter_client            5.2.3                    py35_0  
jupyter_console           5.2.0            py35h4044a63_1  
jupyter_contrib_core      0.3.3                      py_2    conda-forge
jupyter_contrib_nbextensions 0.5.0                    py35_0    conda-forge
jupyter_core              4.4.0                    py35_0  
jupyter_highlight_selected_word 0.2.0                    py35_0    conda-forge
jupyter_latex_envs        1.4.4                    py35_0    conda-forge
jupyter_nbextensions_configurator 0.4.0                    py35_0    conda-forge
jupyterhub                0.9.2                    py35_0    conda-forge
nb_anacondacloud          1.4.0                    py35_0  
nb_conda                  2.2.1            py35hccc8299_0  
nb_conda_kernels          2.1.0                    py35_0  
nbconvert                 5.5.0                      py_0  
nbformat                  4.4.0            py35h12e6e07_0  
nbpresent                 3.0.2            py35h9c03491_1  
notebook                  5.6.0                    py35_0  
pandas                    0.23.4           py35hf8a1672_0    conda-forge
qgrid                     1.1.1                    py35_1    conda-forge
(and many others)

Description of Issue

When displaying time deltas the format is completely off, default pandas rendering in notebook shows something like this:

while qgrid shows something like this:

I would expect something more like the first case in qgrid.

Reproduction Steps

1. Build a dataframe with two columns in a datetime format.
2. Subtract the columns.
3. Display the dataframe.