[buteo-sync-plugin-caldav] Use a time range for quick syncs

Some servers (e.g Memotoo) don't emit a proper reply if we try to
fetch the etags with a defined time range. This commit is a partial
revert of 782ef9db20125f36fec4bbf78ac04a0d335debc7.
Now the client will only store events 6 months older than current date
and 12 months in the future.
[buteo-sync-plugin-caldav] Fix QUrl creating from percent encoded strings

Calendar urls are currently saved in percent encoded format
when passed them in this format to QUrl::setPath a recoding
can happen(Tolerant mode is the default) breaking the original
server path, so we decode them first.
Merge pull request #26 from nemomobile/debugMemotoo

[buteo-sync-plugin-caldav] Use a time range for quick syncs
Merge pull request #27 from nemomobile/calendarNames

[buteo-sync-plugin-caldav] Fix QUrl creating from percent encoded string...
Bump version