Updates for version 0.4.0

This PR is part of the effort to release version 0.4.0.

New Features

Implementation of new manipulation methods: atleast_1d, atleast_2d atleast_3d, expand_dims and append.
Introduction of argmin and argmax methods for CPU.

Fixed a problem where NDArray::transpose on GPU was causing SEGFAULT.
Increases the stability of memory management and allocation of various components through Valgrind's detailed memcheck analyses.
Use of an expandable buffer in the NDArrays print function, avoiding excess null characters and memory waste.
Fixed memory leaks detected by Valgrind in all components.
Fixed an issue where the NDArray::allclose method returned an incorrect result.
Fixed a problem where the NDArray::sinc method returned incorrect values.
Fixed the arginfo of the NDArray::arange method that was causing mismatch.
Changes some tests affected by changes from this MR.
Fixed a problem where the NDArray::allclose method accepted NDArrays stored in VRAM when there was no implementation for that.
Fixed the NDArray::all method that used AVX2 in a suboptimal way.
Fixed an invalid memory read when NDArray::clip received a PHP array as an argument.

General code cleaning, removal of unnecessary includes, variables and allocations.