made roundup part of the source distribution
make roundup path configurable
fix type mismatches and warnings through the code

This is a large set of patches that fixes:

- mismatches between format strings and variables
- 'char' where we meant 'int'
- 'unsigned char *' where we meant 'char *'
- 'long' where we meant 'uint32_t'

...and similar problems.

With this set of patches, Crashmail will now compile with
-Werror -Wall.
compile with -Wall -Werror to catch problems
Add test for dupe handling.
Merge branch 'feature/typefixes' into develop