added triggerSlowSync service endpoint and assistant.

forces next sync to be a slow one, i.e. without
c-tag checks. Helpful if something went wrong,
but c-tag still is ok...
added _saveErrorState method

method makes sure that error state is saved in
database. This ensures that slow sync is happening
on next sync if something goes wrong. Hopefully
resolves some random issues.
corrected content-length calculation.

Additionally content-length is now always set.
Some servers wants them even for DELETE with empty
bodies... Shouldn't hurt.
fixed issue in folder duplication

made it much more robust, too.
This should fix the issue with ownCloud (again).
made setHostAndPort more robust.

Also now stores old protocol, i.e. https or http.
CalDav methods can now handle complete URI in path.
CalDav.deleteObject signature adjusted

also syncAssistant will check result of
delete operation now.
discovery: prevent duplicates for .well-known paths.
CalDav.getFolderList: fixed two issues

both issues let to duplicate folders in results.
finally found typo that let to hang in getFolderList

AHRG.. ;)
SyncAssistant.getNewRemoteObject split up

getNewRemoteObject now again does what it is supposed
to do from the framework point of view.

Created a new method _findURIofRemoteObject which
determines the URI in the different possible cases
during upsync.
add uId for upsync.

Fruux-Server complained, if we left out UID on new
objects during upsync.

This currently works only for calendarevents...
renamed _updateConfig to _updateCollectionsConfig

to reflect what it really does.
added _isOrphanedEntry method

Method checks if DB element belongs to a valid
collection. If not the object probably is orphaned.
In calendar these objects show "undefined" as their
calendar...
This probably happens if calendars are deleted and
recreated.

Orphaned items will get deleted during sync now and
are not used to compare against remote objects, so
if they are still on server, they will get redownloaded,
for example when folder URI changed or event was
moved from one calendar to the other.
during upsync copy new URI from server to local object.

If we got redirected by server this will prevent
deletion and re-download of new object.
BREAKING CHANGE: changed URIs to include host

This might fix the issue with multiple accounts from
different servers. Also it makes redirecting
away from original URL easier.
For example for fruux.com discovery finds
dav.fruux.com/... via .well-known redirects.
But old version did ignore host and tried to talk
to fruux.com which resulted in many errors.

This affects all stored remote objects, because
their remoteIds and URIs were relative, till now.

Two ways to fix:
a. Delete account and start from scratch.
b. 1. Call discovery with correct accountId
b. 2. Call triggerSlowSync

This will correct the URIs for all folders and
re-download all objects again.
corrected some comments in syncassistant.js

Also removed some debug output
(Still VERY noisy...)
postPutRemoteObject now ignores missing etag on save decision