v0.3.6: Improve tester

Stable release, fully backward compatible.

v0.3.5: Dehydrate tester

By means of tester clean up, the environment has been dehydrated too.

Stable release, not fully backward compatible.

v0.3.0: Purity refactor

Purity refactor:

> all math-operators return real array, all math-operators are **pure**
functions.

Why:

+ completely avoid memory leaks;
+ boost performance;
+ parallel-ready.

This change addresses the need by:

+ eliminate all polymorphic, non pure function results.

Side effects:

It could be not fully backward compatible, however it seems quite so.

v0.2.5: Refactor all source-allocations

Refactor all source-allocations by mold-allocations and assigments.

Soucer-allocation generates memory leaks that must be avoided.
Hopefully, mold-allocation/assignment should not.

Stable release, fully backward compatible.

v0.2.4: Add Linear SSP Runge-Kutta class of schemes

Add Linear SSP Runge-Kutta class of schemes: implemented both
s-stage/s-1 order and s-stage/s order methods.

The class provides schemes for any formal order: the coefficients are
computed by means of recursive algorithm (with an original implementation)
that does not allocate unnecessary arrays...

Stable release, fully backward compatible.

v0.2.3: Refactor Oscillation test and improve FOODIE API

Refactor Oscillation test and improve FOODIE API: oscillation test has
been made more self-consistent and easy to use/develop.

FOODIE has been improved providing new procedures (inquiring schemes,
integrators handling, ecc...).

This is **not** fully backward compatible.

v0.2.2: Add SSP Linear Multistep Methods with Variable Step Size

Stable release, fully barckward compatible.