Merge branch 'jk/http-errors'
Propagate the error messages from the webserver better to the
client coming over the HTTP transport.
* jk/http-errors:
http: default text charset to iso-8859-1
remote-curl: reencode http error messages
strbuf: add strbuf_reencode helper
http: optionally extract charset parameter from content-type
http: extract type/subtype portion of content-type
t5550: test display of remote http error messages
t/lib-httpd: use write_script to copy CGI scripts
test-lib: preserve GIT_CURL_VERBOSE from the environment