Closes #1882

Add conversion exception when date and time type convertToDatabaseValue methods are passed non-null values that are not DateTime instances.

- Fixed docblocks
- Removed return statements on void methods
- Cleaned up unused private / local variables
- Fixed license issues
- Removed SVN leftovers
- Fixed doctrine-project.org links
- Added line breaks before return statements

DBAL-26 - Fix nasty bug with null values in Date, DateTime, DateTimeTz and Time fields introduced with the DBAL-22 fix

DBAL-22 - Throw ConversionException if DateTime, Time, Date, DateTimeTz, Array or Object conversions from the Database to PHP fail

[2.0][DDC-354][DDC-425] Fixed. Encapsulated SQL logging better in the DBAL. Added binding types to DBAL mapping types as well as using these binding types in the persisters. Query and NativeQuery now support PDO binding types as well as DBAL mapping types when binding parameters.

[2.0][DDC-92] Fixed. Patch provided by Christian Heinrich. [DDC-274] Started some method renaming. [DDC-142] Fixed (join column names and discriminator column names dont support quoting) [DDC-258] Fixed.

DDC-179 - Fixed issue with persistance of date fields by moving ! operator to the convertToPhpValue method.

[2.0][DDC-30] Fixed null values with Date, Time and DateTime types. Thanks Ismo for report and patch

[2.0] Various necessary fixes and adjustments for oracle as well as fixes for better handling of temporal types. Closed #2452.

[2.0] Implemented DQL bulk DELETE support for Class Table Inheritance. Other cleanups, refactorings and docblock additions.