#12 Small update

Hi,

today I changed a bit the workshop menu to correct some bugs and add a keyboard input field for the number of object you want to add.

Moreover you can now see on the UI a list of the workshops you have created and access them by clicking on it. Also the progress of construction of an building can be accessed by clicking on a building in construction. The field system is taking some time to be done, I hope I can add a first version this weekend.