move v2 api and capi to legacy

User can register a standard C++ functor as Kernel

Change Sprintf back

Change WITH_ANAKIN to OFF

* make transpiler test reliable

* add more

* follow comments

* Shrink reshape_op library size
* User can register a standard C++ functor as a op kernel

Data balance for the ParallelExecutor

add no_random args in fluid_benchmark.py

test reader transpiler

Fix type comparison bugs using std::type_index::hash_code()

Move some v2 codes to a legacy directory.

* Add anchor generator operator for Faster-RCNN.
* Add unittest testing.
* Add Python API.

Add the argsort operator

This is part of big move of v2 codes to legacy sub dir.

Use real test data for fit_a_line model to get valid result