cp filemap/...Table.java multifilehashmap/FileMap

Renamed as it is a different concept.
Copied as there are some changes ahead.
Add MultiFileMap class. W/ cache, w/out any integrity checks
Add size() and list() impl, add integrity check at init
Make check more strict, add clear() method.
Add provider implementation
Add command factory and main. Grand troubleshoot ahead
Grand refactor of factory, enhance exceptions
Fix many bugs.
Add key placing checker
Fix signed chunk number (am i right?)

Posted an issue on this problem:
https://github.com/dkomanov/fizteh-java-2014/issues/284