fix: URLEncoding of query string parameters (#523)

Refactor to get rid of crude and incorrect _appendQueryString. Query string parameter values that can potentially be strings should be URLEncoded. Also, _appendQueryString was assuming that the URL already had a query string and produced invalid URLs if the API version was blank.

Fixes #442, #517
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Co-authored-by: Seva Alekseyev <sevaa@nih.gov>
Co-authored-by: Sebastian Schütze <sebastian.schuetze@razorspoint.com>

Author: 3 people

CHANGELOG.md

@@ -8,6 +8,9 @@ Merged [Pull Request](https://github.com/MethodsAndPractices/vsteam/pull/515) fr
 Merged [Pull Request](https://github.com/MethodsAndPractices/vsteam/pull/508) from [Miguel Nieto](https://github.com/mnieto) the following:
 - Fix import-module loses previously stored configuration [493](https://github.com/MethodsAndPractices/vsteam/issues/493)
 
+Merged [Pull Request](https://github.com/MethodsAndPractices/vsteam/pull/523) from [Seva Alekseyev](https://github.com/sevaa) the following:
+- Fix import-module loses previously stored configuration [442](https://github.com/MethodsAndPractices/vsteam/issues/442)[517](https://github.com/MethodsAndPractices/vsteam/issues/517)
+
 ## 7.12.0