clean up SQLITE3_PREPARE macro for readability
remove pointless BEGIN macro
remove pointless COMPLETE macro
format code block macros for readability

emacs makes it easy to make them look pretty! :-D
add warnings if db file name or password are blank

A database will be created in this case, but it is probably not what the
user intends.
I think you wanted Rationale, in which you explain why this is rational :)