Merge pull request #1 from xhpohanka/for-coretech

Several fixes
PACKAGE: Bump libcurl to 7.33.0
XBMC: Bump to unofficial 12.3
Update README.md
ATV106: Cleanup/prep
openssh: add option to build sftp-server only

Lightweight ssh server implementations (Dropbear) usually lacks sftp
implementation but they can be used with one comming from openssh package.
With this option only sftp-server executable is built and installed into
/usr/libexec.
dropbear: add option to use sftp-server from openssh