[#1687] ticket:574 Remove oauth tokens from preferences
[#1687] ticket:574 Remove ApiToken & ApiTicket
[#1687] ticket:574 Change TestRestApiBase to use oauth
[#1687] ticket:574 Remove RestClient, AlluraImportAPIClient, etc
[#1687] ticket:574 Skip https check during OAuth authentication process, when running tests
[#1687] ticket:574 Fix DuplicateKeyError while creating oauth tokens in tests
[#1687] ticket:574 Remove old tracker import and related tests
[#1687] ticket:574 Remove/fix tests in Allura core
[#1687] ticket:582 Use oauth bearer tokens for AlluraImportApiClient
[#1687] ticket:582 Add upsert to OAuthConsumerToken
[#1687] ticket:582 Add if_missing to OAuthConsumerToken.description

Prevents /auth/oauth/ from raising errors about markdown_html being
absent (may happen when token created without description, e.g. in trac
importer)
[#1687] ticket:582 Use OAuth instead of obsolete ApiTicket auth in wiki-post script
[#1687] ticket:582 Don't check capabilities in discussion import

Since OAuth authentication scheme doesn't support it.
Revert "[#1687] ticket:582 Don't check capabilities in discussion import"

This reverts commit 8f53750ad841cadfc1d8c7a3b3f098339606589f.
[#1687] ticket:589 Add back fix for token creation in tests after revert
[#1687] ticket:589 Check if token allowed to import forum