FIX: in toJSON(), set value to "" if not val instead of str(val)
Merge branch 'v6r11-fixFTS-141003' into v6r11-fixRMS-141013
Also set 'None' to ''
log sensible message
Really hard to set an empty string in that DB!
Avoid 0 to become ''
fix again File.toJSON() for fixing 'None' values
for good?
Remove patches for 'None' and set None to NULL in DB
Merge pull request #2128 from phicharp/v6r11-fixRMS-141013

[v6r11] Fix toJSON() in RMS
v6r11p16
Bug fixed in available()
Empty list of existing pilots is meaningful
Create common catalogs in multi-VO case if VO is not specified
Merge pull request #2135 from atsareg/fix-v6r11

[v6r11] Several fixes
v6r11p17
FIX: in toJSON(), set value to "" if not val instead of str(val)
Also set 'None' to ''
log sensible message
Really hard to set an empty string in that DB!