lib/sqlite3: rename low-level module to native_sqlite3.nit

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
lib/sqlite3: rename classes of sqlite3_native to prevent conflict with Nity versions

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
lib/sqlite3: use a precise type as return of column_type

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
lib/sqlite3: column_text returns a NativeString at low-level

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: rename and update low-level sqlite3 test

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
lib/sqlite3: intro nity interface

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: add a test for the Nity sqlite3 module

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
lib/sqlite3: store and use the error code of a failed database opening

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: test some errors of sqlite3

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
FFI: use libgc allocs

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
FFI: implement the global reference functions

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: test incr_ref with lots of short-lived (in Nit) objects

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
src: new module annoation to help with annotations

Signed-off-by: Jean Privat <jean@pryen.org>
src: use the new module annotation in exising modules

Signed-off-by: Jean Privat <jean@pryen.org>
nitvm: replace hack by incr_refs

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
tests: set nitvm_args3 as undefined

Signed-off-by: Alexis Laferrière <alexis.laf@xymus.net>
neo4j: try to load nodes from `local_nodes`

Avoid duplication of nodes from `load_node` service.

Signed-off-by: Alexandre Terrasa <alexandre@moz-code.org>
neo4j: save and load edges separately from nodes.

Edges must be laoded manually by the user, this allow him to control
the way nodes and edges are loaded in memory and avoir out of memory
exception on big graphs.

Signed-off-by: Alexandre Terrasa <alexandre@moz-code.org>
neo4j: preload data from `nodes_with_label` response.

Speed things a little up with this shortcut.

Signed-off-by: Alexandre Terrasa <alexandre@moz-code.org>
model: implements MType::name

Signed-off-by: Alexandre Terrasa <alexandre@moz-code.org>