Escape special chars, remove old WA for bug in Artifactory

[attiasas]

• [ ] All tests passed. If this feature is not already covered by the tests, I added new tests.

• Escape special chars | , = ; with backslash if not escaped according to: https://www.jfrog.com/confluence/display/JFROG/Artifactory+REST+API#ArtifactoryRESTAPI-SetItemProperties
• Note: character ; that is escaped is not respected by Artifactory setProperties
• Fix bug that for multi value properties only the last value was uploaded by removing old work around.