Improves the `README.md` and merge it with the LICENSE statement.

The license used by this library is a modified version of the
Modelica License 2, this was not clear when pointing to the original
modelica.org hosted version. Therefore those references were removed.
That little text included in README.md. It might be a good idea to
recreate `LICENCE.md` but this time containing the full licence text as
written in `OpenHydraulics.UsersGuide.ModelicaLicence2`
Corrected the release dates.
Fixed a bug in Reynolds number calculation

The flag `use_Re` calls an unknown function if it is set to `true`.  This fixes it by qualifying the function name so it can find the Modelica function.  Otherwise, Dymola falls back to assuming it is an
external C function (which doesn't exist).
Merge pull request #8 from xogeny/missingFunctionError

Fixed a bug in Reynolds number calculation
Merge pull request #7 from dietmarw/improveREADME2

Corrected the release dates.
Merge pull request #11 from harmanpa/master

Bugs in GenericOil, real-equality-with-0
Updated licensor
Merge pull request #13 from kdavies4/master

Updated licensor
Enumeration fixes
- Change .Init to .InitPID where appropriate (the enumerations are different)
- Change integer literals to enumerations (since it is a type error to try to compare integers to enumerations)
Merge pull request #14 from sjoelund/enumfixes

Enumeration fixes
Declare partial classes as partial
Lookup of Toperating is outside scope of functions, changing to constant from parameter
Removed experiment annotation from component models