Enable debugging everywhere by setting DEBUG variables to true.
Hardcode certain settings (user agent, max file size, uaprof, image dimensions, etc.) so iPhone is properly faked to SoftBank. Necessary to avoid 403 error when downloading MMS and getting weird results when MMSC converts message contents.
Dump M-RETRIEVE.CONF to SD Card for debugging purposes.
Retry DNS lookups for MMS proxy and MMSC up to three times because it sometimes fails on SoftBank.

Change-Id: I036c0c095cded75a5d904dba894057e38ce44a68