When we generate random states, for instance when not enough atomic orbitals are available,

Description

When we generate random states, for instance when not enough atomic orbitals are available, the states at the Gamma point are generated as a real function. Otherwise, all the states becomes complex during the SCF, due to the orthogonalization. With this modification, the wavefunctions at Gamma remain real with and without randomization. Note that this is a convenient convention.

News snippet

Changed the behaviour of the states randomization to generate real states at Gamma.

Checklist

• I have checked that my code follows the Octopus coding standards
• I have added tests for all the new features added in this request.