This commit introduces an abstract `BaseContactListAdapter` which provides
most of the adapter logic. The original `ContactListAdapter` extends it to
show date and online status of the contacts.
The new `ContactChooserAdapter` which is used for introductions extends
the `ContactListAdapter` and adds logic for graying out contacts from
different identities than the currently used one.
A new `ContactSelectorAdapter` extends the `BaseContactListAdapter` and
allows to select multiple contacts. It offers a method to return a
collection of all selected `ContactId`s.
This commit also sneaks in an animation when the 'Share Forum' button
is clicked.
Closes#292
When devices' clocks are out of sync, it is possible that a response is
shown before the request. This commit makes sure that the timestamp of
responses is always later than the last message in the conversation.
Some wording could be misunderstood to thing introductions were
successful even though they were not. That has been clarified.
A new database transaction was created when getting contacts and local
transport properties. This has been changed to re-use the existing
transaction.
Also addresses minor issues found in review.
