Changed prices

Prices were out of date, copied from http://aws.amazon.com/s3/pricing/
Minor changes in README to fix points 1 and 2 in my comment at https://github.com/s3tools/s3cmd/pull/369.
Specify content-type for request with XML body

- DELETE Multiple
- PUT ACL
Fixed bug where the error report will not show if there was an import error due to dependency on unicodise which was not successfully imported
Changed the exit code for import errors to not rely on dependency of EX_GENERAL being defined when not imported
Specify default checks performed on files being synced

Debian bugreport: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=534733