Add flags and tests for various multipart evasion techniques.
Detect unknown part headers.
Implement most multipart evasion checks.
Finalize all multipart evasion checks.
Decode C-D header values.
Add a test for escaped terminating double quote in a C-D header value.
Add HTP_MULTIPART_NUL_BYTE, HTP_MULTIPART_INVALID, and HTP_MULTIPART_PART_HEADER_INVALID. With tests.
Do not trim header values.
Stricter checks in the multipart tests.
Handle return codes.
Raise HTP_MULTIPART_BBOUNDARY_NLWS_AFTER for a single dash after a boundary.