sets the default tolerance mode for newly created dimensions.
default and available settings
- nominal* M-^Sdisplays dimensions without tolerances.
- limits - displays dimensions as upper and lower limits.
- plusminus - displays dimensions as a nominal with plus-minus tolerances (the positive and negative values are independent).
- plusminussym - displays dimensions as a nominal with a single value for both the positive and negative tolerances.
- plusminussym_super - same as plusminussym. however, displays the plus-minus tolerance value at the
half-way point of the dimension text and extending upwards.
