FlavorKit Download and Installation

FlavorKit involves several public codes. We proceed to describe how to download and install them.

FeynArts /FormCalc FeynArts and FormCalc can be downloaded from www.feynarts.de/

It is also possible to use the script FeynInstall, to be found on the same site, for an automatic installation.
'''SARAH and PreSARAH ''' SARAH can be downloaded from sarah.hepforge.org/

No installation or compilation is necessary. Both packages just need to be extracted by using tar.
```
> tar -xf SARAH-4.2.0
> tar -xf PreSARAH-1.0.0
```
PreSARAH needs the paths to load FeynArts and FormCalc. These have to be provided by the user in the file PreSARAH.ini
```
FeynArtsPackage = "FeynArts/FeynArts.m";
FormCalcPackage = "FormCalc/FormCalc.m";
```
This would work if FeynArts and FormCalc have been installed in the Application directory of the local Mathematica installation. Otherwise, absolute paths should be used, e.g.
```
FeynArtsPackage = "/home/$user/$path/FeynArts-3.7/FeynArts.m";
FormCalcPackage = "/home/$user/$path/FormCalc-8.1/FormCalc.m";
```
SPheno : SPheno can be downloaded from spheno.hepforge.org

After extracting the package, make is used for the compilation.
```
> tar -xf SPheno-3.3.0.tar.gz<
> cd SPheno-3.3.0
> make
```

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