Config: converted base object to use Moo

- get/set/defined still use the hash-based storage implementation
INIFile: closes #8; added write/dump database schema methods
db_bootstrap.pl: call write INI method after checksumming
wadindex_schema.ini: closes #9; added "default" config block

- Hitting a problem where comments before the first schema section
  disappear when writing out to disk.  Added a "default" config block
  to see if this fixes the issue.  Also added "schema_date" and
  "schema_notes" keys to the "default" block, might as well use it for
  something
wadindex_schema.ini: move 'default' keys, remove whitespace
wadindex_schema.ini: more whitespace tweaks
wadindex_schema.ini: update of file after checksumming
db_bootstrap.pl: add call to dump_schema for --create-db
INIFile: fixes: #8; update 'schema_date' when generating checksums