* Add license to the top of files

* Add licenses agreement on the demo files

* Provide demo code how on to create text records.

* Remove test code

* Complete audio data integration:
* Add num channels, sample width, sample rate as params
* Generate audio file with proper params

* clang format

* Adjust the sync_cycle automatically.

* Change the multiplier type to double.

* Adjust the sync_period.

* Fix comment.

* Add the pre-commit

* Run pre-commit with other files.

* Update the version number
Update the doc to include Vue
Update the doc to give more details on the sync_cycle
Update the doc to include python 3

* Update the LogWriter constructor doc.

* Update the package copy directory.

* Update the version to 0.0.2 (implying beta now)

* Update the vdl_create_scratch_log to python 3 as well.

* Display documentations of demos on the Docs.

* Rename the title from `demos` to `Examples`.

* Provide English tutorial on how to use VisualDL in Keras

* Add the English Tutorial of PyTorch.

* Add the English MXNet tutorial.

* Remove links in the MXNet tutorial.

* rename vdl_scratch.py to vdl_create_scratch_log

* Simply replace the vdl_scratch.py

* Binary Record Fixes

* Fixed issues with binary_record.h filename generator method.  std::hash is not consistent across OS.  It will generate different hash's when ran on different OS on the same string.  Change the filename generator to use a static counter.  It will be more ideal to use UUID generator available in boost 1.4.2, however, boost 1.4.2 has problems compiling on c++11 \n* Fix issue with pytorch demo where it logs to the absolute path /workspace

* Fix performance issue on server when server fails to load image file.  Currently server retries an API call 3 times before it fails, at which point it'll sleep the thread for 2 secs.  This becomes problematic when there are alot of SDK errors.  I'll create seperate issue to refine the retry logic to not be so expensive on the server.

* Add C++ and python style check to travis.  
* Update all C++/python code that violate coding standards.

* support manylinux build

* mxnet graph

* long graph

* added full graph

* add gif back

* updated gif

* fix comments

* remove python highlight for one line

* demo mxnet

* test refer local file

* to english

* link anchor

* anchor should work

* anchor to lower case

* pylint

* init paddle

* add image writer

* change sample numble to 4

* add image and conv image

* add histogram

* rename test file