Added getter for cell contents to CGridColumn

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

issue #106
Enhance CJSON with JsonSerializable support (#2540)
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.
Issue #2653: updated Markdown Extra Lib to version 1.3
Add RESTful method support for html forms

This commit allows calls to `CHtml::form()`, `CHtml::beginForm`
`CActiveForm::$method` etc to accept verbs other than `post` and `get`,
e.g. `delete`, `put`, `patch` etc

This is implemented by detecting non `post`, `get`, converting to `post`
 and adding a hidden `_method` field, similar to how CSRF protection works.
update changelog
Detailed explanation of $cryptographicallyStrong param in generateRandomBytes().
Merge branch 'master' of git://github.com/yiisoft/yii into 2053-corrections-to-random-getters-see-PR-2604-discussion
Nonsense removal
Fixes #2662, reverts #1622:

1. More edgecase unit tests for CLocale.
2. Fix #2662.
3. Revert #1622.
Merge remote-tracking branch 'origin/pr/2697'
Fix indentation for #2697.
Fixes #2691. More descriptive exception message.
Updated russian phrases.
Fixes #2690. Erroneous CSS declaration.
Update readme.txt

PHP version was backwards.
Merge pull request #2702 from bitclaw/patch-1

Update readme.txt
Revert "Merge pull request #2702 from bitclaw/patch-1"

This reverts commit ee57245edecd6c2e7c2cd48a74ccd806b29b3a7c, reversing
changes made to 1466f7d70a6f3baa441fbc1058a0180e4d0dfd7c.
Update finnish translations
Update translations based on @Crisu83 's comments.