[packaging] Created rpm subdirectory for tar-git

Signed-off-by: Juha Kallioinen <juha.kallioinen@jollamobile.com>
[modes] Remove sb2 modes from sdk-sb2-config

Use scratchbox2's own obs-rpm-* modes by symlinking sdk-build,
sdk-build+pp and sdk-install correspondingly.

sdk-manage: cd to the target directory not needed when installing
packages to an sb2 target.

Signed-off-by: Juha Kallioinen <juha.kallioinen@jollamobile.com>
[cleanup] Moved files that get installed under /etc to etc subdir

Signed-off-by: Juha Kallioinen <juha.kallioinen@jollamobile.com>
[rpm] Updated rpm URL string, fixed changelog lines

Signed-off-by: Juha Kallioinen <juha.kallioinen@jollamobile.com>