Improvements and fixes

• Replace SMSGatewayV10EndpointService with including the necessary classes in Intelecom\Intelecom_SMSGW to avoid SOAP dependency.
• Correct casing for originatorTypeEnum constants.
• Specify default null for message settings

Bug fix release

• Update dependencies in Composer
• Improve request error handling

Initial release

Merge pull request #1 from Intelecom/fix-travis-url

Readme: fix travis url for link