Drag and drop function in cataloguing worksheet

During the cataloging process, when the user is on the cataloging worksheet, it will be possible to drag and drop the tag to change its order in the sequence of tags.

Example 1 --> after tag 245, 250, 300, I can have two tags 500:

500 ## $aTest 1
500 ## $aTest 2

In this case the user can choose to move the second tag (with $aTest 2) before the first tag 500.

Example 2 --> after tag 245, 250, 300, I can have several tag :

500 ## $aTest 1
500 ## $aTest 2

In this case the user can choose to move the second tag (with $aTest 2) before the first tag 500.

The user cannot change the sequence order of MARC21 format. We mean, for example, that tag 600 is displayed always before tag 610.
The user can change the order within the same tags categories. So he can change the sequence order of several tags 500, or of several tag 650 or 700 and so on.

So, if I have in a record a sequence of subject tags as:

600 14 $aCCCC
630 04 $aXXX
650 24 $aDDDDD
650 #1 $aZZZ
650 #4 $aYYYYY

I can move the last tag 650 #4 $aYYYYY from the last position to the third:

600 14 $aCCCC
630 04 $aXXX
650 #4 $aYYYYY
650 24 $aDDDDD
650 #1 $aZZZ

But I cannot move it at the beginning of the sequence of the subject tags, because are different categories.