Misc Design Office Improvements

[milspectacular]

• [x] generating a thumbnail image on submission
• [x] Transparent pixel/delete pixel in edit mode
• [x] ability for officers to merge designs with baseline
• [x] change panning to right click and drag so that left drag can be used for painting
• [x] format the cards to horizontal boxes
• [x] fix resizing issues of viewport
• [x] fix displaying white areas where the grid isn't rendered
• [x] a warning prompt when deleting a design, or when exiting design mode with unsaved pixels
• [x] more tools in edit more (eg. rectangular selection/paint, or copy and paste rectangular selections)
• [x] the ability to edit the name of a design
• [x] Ability for officers to edit the colour palette (add, remove, edit, reorder)
• [x] switching between main and expansion baselines based on alert status
• [x] #53