Re-enable Michel's improvements to ncm-accounts.

Revert "Merge pull request #8 from piojo/revert-ncm-accounts"

This reverts commit 760af4d31ebe8bb0b3989bd7d1979d0eba4b4236, reversing
changes made to 15bf89bf65f8186ac54448ffdfc0444526a4184d.
ncm-accounts: Fixes for existing unit tests to make them compatible with last changes
Use the standard header.
Use Readonly hashes for the login.defs mappings.
Fix bugs in the handling of special lines.

There was a mismatch between _shadow_special_lines and
_shadow_special_lines_ . The new code is simpler, too.

Tests are adjusted to reveal the proper handling of these new fields.
Fix bugs and warnings in tests and shell management
Remove spurious check for a NoAction flag.

`--noaction` in this case is handled directly by the CAF file handles.

Blocking the execution of commit_configuration prevents the admin from
seeing the diffs of any files.

CAF::File* guarantee nothing will be changed in the system.

Of course, this assumes the user's perl-CAF and ncm-ncd are less than 3
years old.
Adapt the commit tests to having special lines
Simplify how accounts are committed
Test NIS stuff is added
Use SL5-compatible build tools
Replace Readonly by real constants.

Readonly may not be availalbe on SL5.
Add Michel as a real contributor for ncm-accounts
Fix missing preserved_accounts property in users/consistency.pan test config
Merge pull request #1 from jouvin/ncm-accounts-testing

Fix missing preserved_accounts property in users/consistency.pan test config
Recover the version for easier testing
Merge pull request #20 from piojo/ncm-accounts-work

Many improvements for ncm-accounts