Using openAuth function for authorities Searching

Using openAuth function for authorities Searching

Adding two js functions :
getSubfieldcode(tagsubfieldid)  returns the subfieldcode from tagsubfieldid
(tag_XXX_subfield_Y_WWWW_TTTT returns Y)
getTagInputnameFilter(tagsubfieldid)
(tag_XXX_subfield_Y_WWWW_TTTT returns tag_XXX_subfield_._WWWW)

I think those two functions are much useful when cataloguing.

openAuth now takes all the information for Heading search of authorities.

TODO A javascript DOM Navigation would be better.
This js works, but is surely slower than DOM would be.
Still, it seems that our DOM tree is quite hard to decode.

Signed-off-by: Galen Charlton <galen.charlton@liblime.com>