macros in spec

Signed-off-by: Denis Zalevskiy <denis.zalevskiy@jolla.com>
[rpm] flexible provider-action

arguments supplied to the action script can overwrite defaults

Signed-off-by: Denis Zalevskiy <denis.zalevskiy@jolla.com>
[rpm] improvements in macros

Signed-off-by: Denis Zalevskiy <denis.zalevskiy@jolla.com>