svn: Refactored CertificateCallbackCase - removed logic that ensures not more than one "accept certificate" request per svn command line client call (such logic is unnecessary as currently new callback instances are created on each svn command line client call)
svn: Refactoring - extracted common logic for configuring HttpClient instances with IDEA proxy settings, removed duplication
SMTestProxy: javadoc added
svn: Implemented ability to check and trust server certificate (for https protocol) without utilizing SVNKit authentication lifecycle - request is issued to the server and special TrustManager performs necessary certificate checks
Merge branch 'svn_18_3'