Added getter for cell contents to CGridColumn

Added getters to CGridColumn to allow getting cell contents
for extended use cases of CGridView.

issue #106
Consistent getting table schema in CActiveRecord

$this->getMetaData()->tableSchema replaced with $this->getTableSchema() in CActiveRecord::insert(), CActiveRecord::getPrimaryKey() and CActiveRecord::setPrimaryKey() to match usage in other methods.
Ability to substitute model attribute name, to use custom data getter. It is not dangerous to use any custom fields and getters, because it will work for read-only.
fix #2378 CActiveRecord::tableName() in namespaced model
removed occasional FormInput file
cache dir creation with correct file mod
added options to set mode (used by mkdir and chmod)  for cache directory and files
changed formatting
added tests for CFileCache cacheFileMode and cachePathMode
added CHANGELOG line
Private method 'CFileHelper::mkdir()' has been converted into public 'CFileHelper::createDirectory()'.
CHANGELOG has been updated.
Doc comments at 'CFileHelper::createDirectory()' has been fixed.
Chapter 'Using 3rd-Party Autoloaders' has been added to guide
Merge pull request #2827 from klimov-paul/enh-file-helper-create-directory

Enhancement: CFileHelper::createDirectory
Handle thrown exception in widgets when 'captureOutput' is set to true.
Code formatting
Changelog update
Changing from "ob_end_flush" to "ob_end_clean"
fixed formatting, adjusted changelog