Added registration form and user flow for experiments

• Added a form to register experiments
• The user flow has been modified to be able to create instruments or experiments according to the decision that was taken at https://phabricator.wikimedia.org/T373466 (two different buttons). Header still needs some refinement

• Added agent_client_platform_family by default while registering instruments (related to what we discussed regarding https://phabricator.wikimedia.org/T374116). Some details about this will be added to that ticket
• Catalog view works for baseline instrument and experiments
• Common actions (enable/disable and delete) are working for baseline instruments and experiments

• Experiments and baseline instruments can be updated
• Took the opportunity to remove some not needed fields from /api/v1/experiments response: schema_title, stream_name and schema_type
• Test cases are still pending (follow up ticket?)

Pending work (already discussed in the respective tickets):

• I don't know why but experiments form is wider because of the big warning message we have (before this change the only form we had was also bigger than the baseline instrument one we have right now). We have already discussed it and there is already a follow up ticket to cover it
• The new header layout (according to the new user flow) is not done yet. We have already discussed it and there is already a follow up ticket to cover it
• The new look and feel for the Location component is not included yet with this MR. We have already discussed it and there is already a follow up ticket to cover it

Closes T373467, T373475, T373918, T374116 and T374121