readable receipt file names in default export

[MarcusWolschon]

Is your feature request related to a problem? Please describe.
When exporting a single or multiple/all receipts, the individual zip files are currently just named 1.zip, 2,zip, 3.zip,...

Describe the solution you'd like
The name of the receipt with all illegal characters removed and a length limit should be used as the file name.
If this causes collisions, either _1.zip, _2.zip could be added as needed or all receipts get their id number as a postfix.

Additional context
This also allows storing some exported receipts on a shared Nextcloud or other file storage that multiple users share.
Each with their own receipt applications (not all of them Tandoor Receipts) or using the receipts manually. (e.g. by having an exported PDF in each receipt in addition to the machine readable version and the image file.)

[MarcusWolschon]

Shell script to rename a directory of already exported 1.zip 2.zip .... into readable .zip file names that Tandoor will still recognize

for file in *.zip ; do 
   mkdir temp ; 
   cd temp; 
   unzip ../$file ; 
   NEWNAME=$(cat recipe.json | sed -e "s#{\"name\":\"##" | sed -e "s#\".*##" | sed s/[ä]/ae/g | sed s/[ü]/ue/g | sed s/[ö]/oe/g | sed s/[^a-zA-Z0-9_]/_/g) ; 
   cd .. ; 
   rm -r temp ; 
   mv $file $NEWNAME.zip ; 
done

[MarcusWolschon]

Proposal:

In cookbook/integration/default.py line 59 use the sanitized receipt name

[MarcusWolschon]

Issued a pull request with a fix:
#1280

[vabene1111]

i think i want to add a "slug" field to recipes which should be unqiue to a recipe. This would also allow to link recipes together after an import, that is currently not possible.

i will merge the PR for now as i think this is already an improvement but in the long run i will rewrite this to a "slug" system