Print error reading manifest file.
WIP:  handle missing sbt files
remove simplified check for file exist
Modify SortedBlockTable to detect missing file and behave like it's empty
Set SortedBlockTable file stream options on Config object
Don't run test 4 times under normal circumstance
Test to make sure manifest is rewritten and missing file references are cleared
Add logger ability to sorted block table
Merge branch 'NCover'