[osis-core] Grains with puncuation.

[Todd Tillinghast]

I am working on the following example:
Matt. 19: 16, 21   "What good thing shall I do to obtain eternal life?"
Jesus said to him, "... come, follow Me."

The trouble is that it is natural to encode:
<seg>Matt 19: 16, 21 <reference
osisRef="Matt.19.16@s[what]-Matt.19.16"/> <reference
osisRef="Matt.19.21-Matt.19.21@s[him,]"/><reference
osisRef="Matt.19.21@s[come]-Matt.19.21"/></seg>

The trouble is that "him," is not valid within the [] due to the ",".
Are we stuck with a character point grain (cp) if we need to include a
punctuation mark?

I am hesitant to suggest that we allow punctuation marks in the grain
string because it would be nice to reserve them for other purposes
elsewhere an not require the user to determine if the punctuation mark
character is in between a "[" and a "]".  

This makes the only correct encoding the following:
<seg>Matt 19: 16, 21 <reference
osisRef="Matt.19.16@s[what]-Matt.19.16"/> <reference
osisRef="Matt.19.21-Matt.19.21@cp[18]"/><reference
osisRef="Matt.19.21@s[come]-Matt.19.21"/></seg>

If this seems clear to everyone this may be one for the user manual.

Todd