close #537 by creating an importer for the new format (#538)

* close #537 by creating an importer for the new format

* import from export format

* web handler for importing CREs and standards

* move in memory graph to its own module, add to database module methods for path retrieval and hierarchy retrieval

* remove irrelevant methods from export format, add a check for duplicate links in add_link

* add support for exporting in the new export format

* test for getting cre hierarchy

* add tests for import/export of new format

* add support for new format in main

* web main changes to support new import/export formats

* fix db cre hierarchy retrieval, detect non existent cre

* rm deprecated recursive retrieval tests  from cres, CREs are 1 level deep only

* add test and fix for single cre retrieval

* make write_csv pickup all possible keys from all dicts as a header, add support for new export format to main

* make the memory graph self-initialize, move functionality of get_standard_by_db_id to get_nodes

* update cre exporting method to support new export format not being an enum

add container source label

fix publish action, rename docker tags to all lowercase

rm e2e tests tmp (#524)

disable explorer until we can fix it (#522)

push tags