==== Conventions to force ordering in List of Symbols ====

0 symbol
1 greek
2 roman

the symbol/letter

0 lower case
1 upper case

0 text
1 index
2 scalar constant
3 scalar function
4 vectorial constant
5 vectorial function
6 unit vector
7 tensor
8 set

[the following can be OR'ed]
0 raw
1 decorated
2 indexed
4 subscripted
8 superscripted

[followed by subscript - index - decoration - funcarg]
