Free variable warning about bbdb-version (bug#19678)

[Thomas Fitzsimmons]

Hi,

I'm trying to make eudcb-bbdb.el compatible with BBDB 2 and BBDB 3.  To
check the version, I need something like:

(if (version<= "3" bbdb-version) ...)

but the byte compiler warns:

Warning: reference to free variable `bbdb-version'

I'd rather not introduce a new warning.  Is there a good way to handle
this?  Adding (defvar bbdb-version) to eudcb-bbdb.el seems wrong, since
the version check is assuming it's a constant defined by the external
BBDB package.

(The best solution would be to bundle BBDB 3 into Emacs -- I'm working
toward this with Roland Winkler.)

Thanks,
Thomas