Add code to handle ownCloud servers running on IDN

ownCloud instances can run on servers having an internationalized domain
name. This commit adds a conversion function between ASCII and Unicode.
The conversion function is used in the Authenticator and Preferences
activities.

See issue #469.
update
new url
Download thumbnails from server with rest api
- removed help function
select all / deselect all file in upload menu
Added feature for remembering last upload location when sharing a file. Also added an option to turn it off in prefrences.
Fixed merge
Fixed imports and added comments
Merge branch 'idn_hosts' of https://github.com/ogasser/android into idn_hosts

Conflicts:
	src/com/owncloud/android/authentication/AuthenticatorActivity.java
Added check for that the last upload folder still exists
Merge with develop
- Using Uri.encode...
- Thumbnail size is set to 32dp
- fix bug
- bugfix
Merge with develop
Fixed log import
Removes translations
Removes remember last share location setting
Merge branch 'develop' into idn_hosts