Merge pull request #3 from why404/master

added source doc
new sdk
Merge pull request #6 from hughlv/master

the new objc-sdk
Fixed memory leaks and refactored code.
Added readme.
Updated readme.
Updated unit tests.
Updated unit tests.
Merge pull request #7 from hughlv/master

Fixed memory leak problem.
Supported CRC32.
Replaced appendFormat with appendString for performance concern.
Merge pull request #8 from hughlv/feature/crc32

Supported CRC32.
Merge pull request #9 from qiniu/master

Supported CRC32
Update README.md
Merge pull request #12 from qiniu/develop

rename to ios-sdk