modified bibliography titles

Added @xml:lang and any missing @level attributes to <title> elements
within <bibl> elements, deleted the <choice>/<expan> | <abbr> structure,
and entered the Syriac title for Barsoum Syriac.  I also modified
citations of Abdisho-BO to put Assemani's title as @level="m" and
include the volume number in the <citedRange>, in accordance with the
srophe/bibl entries.
tweaked article separator character in CBSC

tweaked the separator character between article titles in CBSC citations
from semi-colon to comma
20 URL columns -> one URLs column

The spreadsheet had 20 URL columns.  I altered the spreadsheet to have
one URLs column with all of the URLs in it, separated by *double* spaces
(because some URLs contain a single space, which they really shouldn't),
and I altered idno.xsl to tokenize the URLs column to have the same
functionality as the 20 URL columns.  I also cleaned the spreadsheet of
double-spaces in name columns, and the CBSC en-Full column now contains
a semi-colon separated list of CBSC names where there are multiple.
This breaks the CBSC en-Link column formula, but I haven't fixed that
yet.