Including the validation of creation of KPIs and their values to the OFC'22

See merge request !15

Consolidating commong fixtures in a single file at the root of the tests folder. Updating ECOC'22 and OFC'22 tests to use it.

Fixing some imports and branching a fixture file for each test case so that they can have particularities.

Including the validation of creation of KPIs and their values to the OFC'22 test set. Also consolidating the fixtures into a single file in the root of the 'src/tests' folder so that all tests can import from it.

Feat/monitoring major functional updates

See merge request !14

Minor code polishing after ECOC'22 demo

See merge request !13

- improved HTTP status code checks

- minor styling improvements in Slice pages

Merge Hackfest material into Develop

See merge request !11

Tutorials cleanup

See merge request !10

Pass on the tutorials to (i) verify that all parts are complete (did not run the installation procedures); (ii) updated instructions on how to select the Python version; (iii) general aestetic changes.

doc/fix: add instructions for ngsdn-tutorial mininet

See merge request !9

- integrated command files
- moved unused command listings to separate folders
- polished data files
- cleaned up TAPI show topology script and context database
- added TFS descriptor files

NetworkX 22 P4 workshop

See merge request !7

fix(device): avoid conversion to canonical bytes

See merge request !8

Also, remove unecessary conditions prior to rule
insert/update/delete operations

Signed-off-by: Georgios P. Katsikas <gkatsikas@ubitech.eu>

- added bearers for Hackfest

- added MockOSM package

- refined TrandportAPIDriver endpoint retrieval
- refined Driver selection

- added "Delete Service" button

- added basic Netconf/OpenConfig server

- added support for json-formatted custom config rules

- updated tapi_app to plot topologies

- updated TAPI exercise