* src/metalink.h: Add declaration of function clean_metalink_string()
* src/metalink.c: Add directive #include "xmemdup0.h"
* src/metalink.c: Add function clean_metalink_string() remove leading
and trailing white spaces and CRLF from string
* src/metalink.c (retrieve_from_metalink): Remove leading and trailing
white spaces and CRLF from url resource mres->url
* testenv/Makefile.am: Add new file
* testenv/Test-metalink-xml-urlbreak.py: New test. Metalink/XML white
spaces and CRLF in url resources tests
White spaces and CRLF are not automatically removed by libmetalink
from url strings. The Wget's Metalink module was unable to process
such url strings. This patch implements the processing of such url
strings cleaning off leading and trailing white spaces and CRLF.
If a parsed Metalink/XML url string contains strings separated by
CRLF, only the first of the series is accepted.
