In YAML 1.0 the colon is mandatory. See http://yaml.org/spec/1.0/#id2558635.

This also allows prior releases to read YAML files created with the current version.

- one test for type_id;
- another for comments in JSON;

a JSON emitter, a parser, tests and some basic doc.

Major changes:

- modify the Base64 functions to compatible with `cvWriteRawData` and so
on.
- add a Base64 flag for FileStorage and outputs raw data in Base64
automatically.
- complete all  testing and documentation.

I could not find the cause of the error:

```
C:\builds_ocv\precommit_opencl\opencv\modules\ts\src\ts_perf.cpp(361):
error: The difference between expect_max and actual_max is
8445966.0000002384, which exceeds eps, where

expect_max evaluates to 0.9999997615814209,

actual_max evaluates to 8445967, and

eps evaluates to 1.0000000000000001e-005.

Argument "dst0" has unexpected maximal value
```

Hope this is a false alarm.

The three new functions:

```cpp
void cvStartWriteRawData_Base64(::CvFileStorage * fs, const char* name,
int len, const char* dt);
void cvWriteRawData_Base64(::CvFileStorage *
fs, const void* _data, int len);
void
cvEndWriteRawData_Base64(::CvFileStorage * fs);
```

Test is also updated. (And it's remarkable that there is a bug in
`cvWriteReadData`.)

```cpp
cvWriteMat_Base64(::cv::FileStorage & fs, ::cv::String const & name,
::cv::Mat const & mat)
```
becomes:
```cpp
CV_EXPORTS void cvWriteMat_Base64(::CvFileStorage* fs, const char* name,
const ::CvMat* mat);
CV_EXPORTS void
cvWriteMatND_Base64(::CvFileStorage* fs, const char* name, const
::CvMatND* mat);
```

Two other test are still needed.

1. Verify the Base64 data.
2. Read an old YML file for compatibility test.

1. Add Base64 support for reading and writing XML\YML file.

The two new functions for writing:

```cpp
void cvWriteRawData_Base64(cv::FileStorage & fs, const void* _data, int
len, const char* dt);
void cvWriteMat_Base64(cv::FileStorage & fs, cv::String const & name,
cv::Mat const & mat);
```

2. Change YML file header form `YAML:1.0` to `YAML 1.0`. (standard
format)

3. Add test for Base64 part.

[GSoC] FileStorage:
Add base64 support for reading and writting XML\YML file.
The two new functions:
```
void cvWriteRawData_Base64(cv::FileStorage & fs, const void* _data, int
len, const char* dt);
void cvWriteMat_Base64(cv::FileStorage & fs, cv::String const & name,
cv::Mat const & mat);
```

Conflicts:
	modules/gpu/perf/perf_imgproc.cpp

Cast a long integer to double explicitly.

Conflicts:
	modules/python/src2/cv2.cpp

Cast some matrix sizes to type int.

Change some vector mask types to unsigned.

Conflicts:
	modules/core/src/arithm.cpp

1. someMatrix.data -> someMatrix.prt()
2. someMatrix.data + someMatrix.step * lineIndex -> someMatrix.ptr( lineIndex )
3. (SomeType*) someMatrix.data -> someMatrix.ptr<SomeType>()
4. someMatrix.data -> !someMatrix.empty() ( or !someMatrix.data -> someMatrix.empty() ) in logical expressions

Conflicts:

	modules/core/src/stat.cpp

Conflicts:
	modules/core/include/opencv2/core/cuda.hpp
	modules/cudacodec/src/thread.cpp
	modules/cudacodec/src/thread.hpp
	modules/superres/perf/perf_superres.cpp
	modules/superres/src/btv_l1_cuda.cpp
	modules/superres/src/optical_flow.cpp
	modules/videostab/src/global_motion.cpp
	modules/videostab/src/inpainting.cpp
	samples/cpp/stitching_detailed.cpp
	samples/cpp/videostab.cpp
	samples/gpu/stereo_multi.cpp

This and several following commits contain the "boring" changes required
to support the new Ptr. These are changes like:

* new T -> makePtr<T> or .reset(new T) or Ptr<T>(new T)
  (depending on the situation)
* p.empty() -> !p
* delete_obj -> DefaultDeleter::operator()

and similar changes that are numerous, but primitive.

All tests passed!