Handling for error 429 and 500

Merge pull request #95 from mailjet/handling-error-429-and-500

Handling for error 429 and 500

Added V4 and SMS support

• Added support for authentication with bearer token for the SMS API

Fix for float number format properties in contact data

v4.2.1

Merge pull request #90 from systoyanov/83-handle-float-properties-con…

Stats revamp new stats endpoints

Merge pull request #89 from systoyanov/stats-revamp-api-updates

Changes on resources related to "Stats revamp" project

URL encoding of alternate ID

• Fixes an issue when the alternate ID is not URL compliant

Support for Send API v3.1

Add support for Mailjet brand new Send API v3.1 currently in beta. Learn more at https://dev.mailjet.com/guides/?shell#send-api-v3-1-beta

mailjet-client-4.0.5

• add variable in purpose to send many messages with one call ( https://dev.mailjet.com/guides/?java#sending-in-bulk )

v3.1.1

• Better Error management
• ContactManagemanycontacts fixed
• Better response handling to prevent npe(s)

JSON properties are passed by default in UTF8 encoding

v3.1.0

3.1.0

v3.0.0

• Lighter wrapper
• Kept some helper properties
• Google App Engine compatible
• Uses the Google Http Client Library
• Readme cleanup
• Travis integration