Apply workaround fix for replication checkpoints test against R14B01

R14B01 and R14B02 both are affected to OTP-9167 Erlang issue which
causes 4 tests failure because supervisor restarts worker with old
ChildSpec ignoring changes in use_checkpoint options.

This fix makes all tests passed, but leaves a notice in verbose mode
that there is a problem and how it could be resolved.

Another possible solution is to isolate test_use_checkpoints calls, but
this will be only hide the issue while it still may happened in prod.
Move Erlang 17 support to 1.6.0 release
Fauxton: do not underline help icons on hover

Addtionally, use <%- where no <%= is needed
Remove doubled event.preventDefault call
Fauxton: Configurable escaping of notifications

Sometimes we are passing static html-links to the notification-
helper. With the new setting `escape: false` the escaping for
the notifications can be disabled.

The default value is that all values are escaped, as long as
no value with `false` is passed for the option escape.
`undefined` and other falsy values will not unescape.

I updated all occurences where we are passing html to the
notifications, and added a comment, that people are careful, when
the passed message changes to e.g. a dynamic content generated
from users.
Fauxton: fix sorting for tasks on click

there is no node property, but a target, source or database
depending on the task
Fauxton: use .listenTo and not .on

There was no `.off` call on destroy, so these two Eventhandlers
where leaking memory
Fauxton: Extract a common filter component from logs

Create a reusable component from the filter that is used in logs,
that can be used in for tasks like
COUCHDB-2158 ("Apply filter with custom params on changes feed page")
and other situtations where a filter is needed.
Fauxton: fix regression for document editor

Introduced with ebade0f2f82d4da60e386f4aeaf24ecb98181e81
Use `os:timestamp/0 instead of `erlang:now/0`

We don't need the guarantees of `erlang:now/0` in `make_cookie_time/0`,
so `os:timestamp/0` is just fine.
Remove unused variable and function call

Finally get rid of that compiler warning.
Send a real EventSource event for heartbeat

The EventSource connection can get stuck (in TCP half-open state*) and there's no way
for the client to detect that. This commit changes the way heartbeat is sent, instead of
sending a newline character, it sends an empty event of type heartbeat:

    event: heartbeat
    data:

This event doesn't have an id: field, so the client will retain its latest Last-Event-ID state.

This doesn't change the expectations of clients that used EventSource till now, because they
subscribe to the 'message' event type. To get the 'heartbeat' events a client will need to
explicitly subscribe to it:

    source.addEventListener('heartbeat', function () { /* cancel a timer that would otherwise reconnect the source */ });

* this can happen when you suspend your laptop, on flaky internet connection, ADSL reconnect,
bad wifi signals, bad routers etc. Pretty often in a typical internet usage nowadays.
Fauxton: fix loading of pouch

Added a red test which turned green
Support `fail_if_no_peer_cert` ssl option
Rephrase part of the replicator documentation

This tries to make the replicator documentation's "Delegations" section
more clear and easier to read.
Fauxton: reformat code & remove whitespace
Fauxton: refactor ActiveTasks

- do not use a model as a collection, directly operate on the
  collection which gets filtered for the view
- remove the view which acted as layer to fetch collections from
  the model and passed it to a view
- remove not used html-template
- format code
Fauxton: do not load unnessecary d3 & backbone
Fauxton: Hide preview functionality until we improve it
Fauxton: Inject database into view

it's handled in the options and used, but was never passed