update all path buffers to accept long UNC paths
only conditionally call GetFinalPathNameByHandleW(), which is unavailable on XP
Merge pull request #398 from adobe/bchin/issue-6197

Fix for Issue #6197- "Broke Compatibility with Windows XP in Sprint 35"
merging latest master changes and fixing conflicts
Merge pull request #397 from adobe/jeff/fix-5270

Update all path buffers to accept long UNC paths