Fixing installation of registrar source

Adding config schema

Reporting

See merge request !21

# Conflicts:
#   core/registrar.py
#   core/run-registrar.sh

add option for case-insensitive match in unpack

See merge request !19

# Conflicts:
#   README.md
#   core/run-registrar.sh

Preprocessor modularization

See merge request !15

# Conflicts:
#   .gitlab-ci.yml
#   README.md

Fixing testing

See merge request !20

Fixtures for connection and test data
Using dotenv to load env vars

 - proper escaping
 - wrong XML tag

input dataxx/itemname gets uploaded to dataxx bucket as itemname (makes 
it possible to mimic old preprocessor this way in case no bucket set)
motivation in this commit is to AVOID data duplication in new bucket and 
dataxx buckets with possible reprocessing campaing

add product_exists method to check if 2 or more files in target and target.replace configuration default to false