minirst: simplify and standardize field list formatting
The default width of field lists is changed from 12 to 14 to align minirst with
the rst2html tool. Shrinking the width of the left column to fit the content is
removed, to keep formatting simple and uniform.
$ rm -rf a
$ hg init a
$ cd a
$ echo a > a
$ hg ci -Am0
adding a
$ hg tag t1 # 1
$ hg tag --remove t1 # 2
$ hg co 1
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg tag -f -r0 t1
$ hg tags
tip 3:a49829c4fc11
t1 0:f7b1eb17ad24