Release TeraFlowSDN 3.0

Closes #106, #105, #107, #40, #57, #102, #122, #123, #112, #111, #120, #119, #91, #104, #90, #94, #109, #101, #73, #68, #69, #70, #67, #80, #100, #79, #99, #98, #97, #96, #95, #83, #88, #45, #1, and #84

See merge request !235

Merge branch 'feat/155-fix-tfs-api-exposition-in-ingress-controllers-for-multi-tfs-tests' into 'develop'

Resolve "Fix TFS APi exposition in ingress controllers for multi-TFS tests"

See merge request !234

- Fixed modified ingress controller settings to fit with endpoints exposed by NBI component

Merge branch 'feat/152-install-requirements-script-needs-to-be-updated-for-libyang-installation' into 'develop'

Resolve "Install Requirements script needs to be updated for libyang installation"

See merge request !233

Merge branch 'develop' of ssh://gifrerenom_labs.etsi.org/tfs/controller into feat/152-install-requirements-script-needs-to-be-updated-for-libyang-installation

Resolve "Update license headers for Release 3"

See merge request !224

- Updated skip filters

- Updated copyright line
- Updated ignore filters

- Updated copyright line

- Code cleanup
- Not finished

- Corrected regular experssions
- Not finished

- Added missing skip patterns
- Added multiple old copyright lines
- Added logic to keep new-line chars
- Not finished

- Updated file mode update in update_license_headers.py script