shift template creation - improvement suggestions - v16

[polchampion]

The shift module was recently ported to v16 in #504.

Two small issues concern shift template creation :

1. No "create" button appears so long as no "Day" column has been created. However, days configured in the settings do not show up as columns until one shift template is created with this "day".
   

2. The "create shift template from type" wizard's display should be improved.
   

[polchampion]

@victor-champonnois fyi