- replace `assign` method with a high-level API

* add access function to IndexIVF;

* - access for IndexIVF;
- write_index/read_index with std::function<...>;

* - fix test compile on mac;
- adjust write/read with std::function;

* replace std::function with IOReader/IOWriter;

* remove IndexIVF::access // tmp

* PFN_WRITE/READ => WRITE;

* revert mac compile fix;

* rename;

* fix compile;

* reset CMakeList;

* format; remove unused function/header;

- change libfaiss_c.a libgpufaiss_c.a targets to only include wrapper
impl
- include libfaiss_c.a on c_api `make all`
- build libgpufaiss_c.so with libfaiss_c.a instead of faiss_c .o file list

CMakeLists.txt, so we can install the libs and headers with make
install.

leftover include file

* [c_api] leverage index downcast

- make index downcast declaration+definition possible with macros
- use macros on existing index types

* [c_api] Add IndexLSH to C API

* [c_api] Add Index IO interface

- new header index_io_c.h for access to the index_io.h API
- function`faiss_write_index` and overloads for dumping index to a file
- function`faiss_read_index` and overloads for reading index from a file
- function`faiss_clone_index` for cloning an index
- update C example to save index to a file

* [c_api] Add IndexIDMap and IndexShards API

* Implement remove_ids in IndexPQ

* Update IndexPQ.cpp

* Remove useless LIBNAME macro in Makefile.

* Add installdirs, install, and uninstall Makefile targets.

* Fix merge.

update faiss.py to enforce less strict check of error message

thanks. Also addresses #392

Not tested but looks legitimate + better than previous state in any case ;-)

* :update Readme to include conda install info

* move to INSTALL.md

* Add C API

* Add installation instructions for the C API

- support on-disk IVF

* Add shared lib target for GPU version.

* Dynamically link tutorial examples.

* Add shared lib to clean target in GPU Makefile.

* Add clean target to tutorial examples Makefile.

* Minor modifications to tutorial GPU examples.

Update Getting started tutorial link.

* Remove transitional print import.

* Add example for multiple GPUs in python.

* Add example on GPU in C++.

* Add example on multiple GPUs in C++.

* Add IVFFlat example on GPU in python.

* Add Makefile for C++ tutorial examples.

* Add IVF index on GPU example in C++.

Add template for issues.

ok