Multi-part form parsing code for REST api responses and mime data

handles parsing multi-part forms from response body in a REST api into the different parts including each part's headers and body.
Original version by Daryl Foster.
Contains 2 nvo objects: the multi-part form parser and the objects that get created for each part.
Utilizes content-length if available in the header.

The actual encoding used should be in the header of the main rest response. That would need to be set as needed prior to parsing the object. Assumes UTF-8 if not set.

sample usage:
<sub>...
inv_http.GetResponseBody(lblb_blob)
ls_content_type = inv_http.getresponseheader( 'Content-Type' )

ls_boundary = lnv_multi_part_extraction.of_GetBoundary(ls_content_type)
ll_parts = lnv_multi_part_extraction.of_Parse(lblb_blob, ls_boundary) // n_cst_multipart by Daryl Foster

// Get part 1 - assumes json here
ls_content_type = lnv_multi_part_extraction.io_parts[1].of_GetHeader('Content-Type')
ls_Content_Length = lnv_multi_part_extraction.io_parts[1].of_GetHeader( 'Content-Length' )
ls_ReturnJson = string(lnv_multi_part_extraction.io_parts[1].iblb_data, iencoding_ ) //if it is json

// Get part 2
ls_content_type = lnv_multi_part_extraction.io_parts[2].of_GetHeader('Content-Type')
ls_content_disposition = lnv_multi_part_extraction.io_parts[2].of_GetHeader('Content-Disposition')
ls_Content_Length = lnv_multi_part_extraction.io_parts[2].of_GetHeader("Content-Length")
ablob_image = lnv_multi_part_extraction.io_parts[2].iblb_data //if it is an image</sub>

more info:
community.appeon.com/index.php/qna/q-a/h...tipart-response-body
stackoverflow.com/questions/4238809/exam...-multipart-form-data