- added property $request_timeout to control the cURL option CURLOPT_TIMEOUT, contributed by @mreho
- added setter and getter for $request_timeout, contributed by @mreho
- changed default value for the cURL option CURLOPT_HTTP_VERSION to CURL_HTTP_VERSION_1_1:
- as of cURL version 7.62.0 the default value is CURL_HTTP_VERSION_2TLS which may cause issues
- https://curl.se/libcurl/c/CURLOPT_HTTP_VERSION.html
- added property for $curl_http_version to hold the value for CURLOPT_HTTP_VERSION
- added setter and getter for $curl_http_version
- switched to using a constant to hold the class version
- updated the README file
- increased minimum required PHP version to 5.5.0
- minor syntax improvement based on Scrutinizer feedback
- added create_dynamicdns() and set_dynamicdns() methods, "borrowed" routes from @smos
- added set_element_adoption() method, contributed by @VWT-Dan
- made a start at changing the function/method comments to PHPDoc format (PSR-5) which will support auto-generated class documentation (https://github.com/php-fig/fig-standards/blob/master/proposed/phpdoc.md#5-the-phpdoc-format)
- added check to throw an error when the $baseurl ends with a / character, thanks to @infraweavers for submitting #66
- fixed issue with logout() on UDM PROs, thanks go to @Olivier6767 for providing access to a UDM PRO, addresses #63
- applied several code styling improvements
