Rename module deps/eigen3 to deps/eigen3/3.3.9, add new module deps/eigen3 redirecting to deps/eigen3.3.9 on bionic, apt/eigen3 else

dbs/research_projects/eurobin: Remove unneeded environment variables overriding used ones

See merge request !492

Move euROBIN modules to external DB

See merge request !490

tools/nodejs/*: Add modules for node and npm

Closes #276

See merge request !489

armarx/skills/control: Remove constraint of building project with 4 jobs

Closes #275

See merge request !488

OS-specific apt CI caches and pip CI caches

See merge request !487

armarx_integration/robots/armar6/*: Add ARMAR-6 Models module

See merge request !486

deps/embedded_template_library: Add embedded_template_library module

Closes #274

See merge request !485

Enable apt caching, clean up pylint job

See merge request !484