Reopened Issue: [pykd-0.2.x] pykd blocks pdb files [11665]

1. run script and get typeInfo from a module
2. call .reload /u windbg command
3. try to delete module.pdb file (for example, rebuild module)
Result: module.pdb can not be deleted

4. .unload pykd and try delete the file another time
Result: module.pdb is deleted successfully