result of sorted volumes is wrong

The attribute order of mods:part hast to be a positive integer.
As I can see the belonging database field is
tx_dlf_documents.volume_sorting - but it is of the type tinytext.
As a consequence the result of sorted volumes is wrong like this:
[...]/390/40/400/450/50/500/[...]
http://resolver.sub.uni-hamburg.de/goobi/PPN637205685
So I use "CAST ... AS UNSIGNED" to get a correct volume list but it
would be better to change the data type of the affected database field.
Revert "result of sorted volumes is wrong"

This reverts commit 330aba5ec981e43e11e0fbd1b2ce3aebf3c4c576.
override SOLR default value for facet.limit of 100

If you want to make for example an alphabetical index of persons, you
need all entries of the selected facet "persons". If you set
"limitFacets" in the typo3 backend, the maximum value is 100. I think it
is inconseqent to offer the possibility to set this value - but only
until 100.
If you need more than 100 entries for a facet, you have to set
facet.limit of SOLR because by default facet.limit=100.
Merge pull request #16 from KatharinaLemke/fix-facet-limit

Fix facet limit