HTML descriptions updated

Enhancement: Adding a opening with analytical calculation of the mass flow rate with respect to pressure (static and hydrostatique)

Error correction: wrong expression for mass fraction in the mass flow vector at ports

Modification to avoid issues when having a medium where the massFraction_pTphi function does not exist

Modification to taken account of buoyancy when gas with a lower density is at the bottom of the opening.

Correction: Mistake on sign of power. The power is positiv when exchanger cools the fluid A and heats up the fluid B

Correction: water inlet of the sensible part when the exchanger is considered as wet is TB_mid_2 and not TB_in

Correction of path to saturation function because old path derived from a partial package. This is no longer allowed

        substance notably):
                + atmosphere (source within fluidDynamics)
                + Opnening : compute X with 1 substance medium

        + combine vertical, simple and horizontal opening
        + ease specification of areaulic case and avoid mistake leading
        to unphysical air movment

        + remove initial equation (initial purpose was to help
                initialization by provided inverse function of homotopy
        + enable user to set T/deltaP ref used to compute damper Kv
        + fix homotopy simplified expr (to compute mass flow based on
            Kv)

Removal of reference to state.X in openings to be able model Medias without the mass fraction in their ThermodynamicState record

Correction of a mistake in the calculation of the default value for the base surface area of the volume

Dymola compatibility: Move of statements regarding transport_A&B input from the equation section to the inside of parenthesis in the class declaration statement

Dymola compatibility: Correction of wrong statement when redeclaring a class (replaceable instead of redeclare)

Dymola compatibility: Correction of wrong statement when redeclaring a class (replaceable instead of redeclare)