Do not show links or buttons unless the user has corresponding level

[gbdrm]

User should have more and more abilities with every level.

Level 0 or not signed in user - User should have full access only to sparks and About page.
When user navigates to other section, like: Projects, Community, Quests, Skills - there should be a disabled view.
Level 1: Add ability to view projects. The View is not disabled anymore.
Level 2: Add ability to view Skills page without disabling it.
Level 3: add ability to add a project. So, do not show the button to add a project, unless the user is at least level 3.
Level 4: add ability to add a spark. So, do not show the button to add a spark on sparks page, unless the user is at least level 2, idea spark should be still possible to add, but the category should be Idea only, no option to change it when adding Idea spark.
Level 5: Enable quests.

Feel free to complete this task step-by-step.