New discovery logic

[timea-solid]

Update of discovery logic of typeIndexes and preferenceFile according to https://github.com/solid/webid-profile spec. Main work was done in solid-logic. see: https://github.com/SolidOS/solid-logic/issues/42 PRs:

• [x] Solid-logic PR: https://github.com/SolidOS/solid-logic/pull/44
• [x] pane-registry PR: https://github.com/SolidOS/pane-registry/pull/23
• [x] solid-ui PR: https://github.com/SolidOS/solid-ui/pull/504 (branch has a different name but it is the correct one - prune-delete it is called.)
• [x] https://github.com/SolidOS/activitystreams-pane/pull/16
• [x] https://github.com/SolidOS/chat-pane/pull/81
• [x] https://github.com/SolidOS/contacts-pane/pull/68
• [x] https://github.com/SolidOS/folder-pane/pull/32
• [x] https://github.com/SolidOS/issue-pane/pull/59
• [x] https://github.com/SolidOS/meeting-pane/pull/49
• [x] https://github.com/SolidOS/profile-pane/pull/38
• [x] https://github.com/SolidOS/source-pane/pull/34
• [x] https://github.com/SolidOS/solid-panes/pull/354
• [x] https://github.com/SolidOS/mashlib/pull/165
• [x] https://github.com/SolidOS/solidos/pull/169

This new discovery and refactoring will solve: https://github.com/SolidOS/mashlib/issues/79 and possibly also https://github.com/SolidOS/solidos/issues/66