The general purpose method function featuresComply() is now capable of
returning a list of features failed compliance check. See -inactive key
of function paramters hash.

- Documentation changes.

Done via @FS_REQUIRED extension's module array. Supports -namespace.

…to Item14237

* commit 'a6cf48d55bcd4fe99d8760369acadeab9c7a02ff':
  Item14152: Implemented long forgotten feature compatibility check.
  Item14152: Added possibility to get a list of inactive features.

First practical extension ever. Read/write database config. Does not
override file-based LSC as the latter is used as a bootstrap and first
stage config. It is anticipated that tricks with setlib.cfg,
LocalLib.cfg must be obsoleted by now due to working combination of
initial path guessing and very early reading of LSC.

- Support for automatic creation of a missing file.

- Added flag attribute 'autoCreate'. Indicates that the file must be
created if missing.

- Added 'modified' attribute which is set to true if file content has
been changed.

writeLSC and readLSC are now generic methods utilizing
(read|write)LSC(Start|Record|Finalize) methods to do the actual work.
This simplifies creating extensions implementing different backends. See
DBConfigExtension for an example of such backend.

…ife.

- Config and extensions are now being loaded in a two-stage process
where first basic config class is used to initialize the config. Then
extensions are loaded. After that the process is repeated but at this
point the config could be loaded with a help of an extension.

- Added 'initStage' attribute to inidicate what is the current stage of
app initialization. Makes sense until contexts could be used.

- Added declaration of OOSPECS feature.

- Fixed a bug with deep recursion in create() method.

Or we may hit deep recursion issue.

- Doc fixes

- Configure Save wizard calls writeLSC() method alongside with writing
to LocalSite.cfg. This is a temporary test measure until Configure makes
use of the new specs format.