- New global variable `extra_pth_drill` defines how much the drill will
be enlarged for plated holes.
- Removed all *_1* report values.
- Added *_real* report values. They are the asjusted drill values.
- Now we compute Eurocircuits Drill Class using all the real drill
sizes.
- Documented all global variables/options.
- Added command line option to list all global options.
- Adjusted the report templates and thei references.
Related to #164