A bit doc.
Rename process_finish() to process_replace().
cf-upgrade shouldn't include from lmdb, postgres etc.
Preserve environment through exec.

For example dpkg requires PATH environment variable.
Silence a number of compiler warnings.
Merge pull request #1783 from vohi/compiler_warnings

Silence a number of compiler warnings.
Merge pull request #1774 from jimis/cfupgrade

Simple doc, Makefile, and cherry-pick error fixes.