build: Reformat resource/c_common SConscripts

build: Reformat resource/c_common SConscripts

[Mats Wichmann]

Reformat all of the resource/c_common SConscripts to be more Pythonic

There are not intended to be any functional changes
The test harness is now consistently imported as:
  from tools.scons.RunTest import run_test
rather than import * - should normally avoid importing whole
  namespace unqualified unless it is really needed

[Philippe Coval]

Ported to 1.3-rel from master

Conflicts:
	resource/c_common/unittests/SConscript

Change-Id: I7957659932535f63f7e3e98a786b997c6a0dca3b
Signed-off-by: Mats Wichmann <mats@linux.com>
Origin: master
Bug: https://jira.iotivity.org/browse/IOT-1745
Signed-off-by: Philippe Coval <philippe.coval@osg.samsung.com>
Reviewed-on: https://gerrit.iotivity.org/gerrit/20573
Tested-by: jenkins-iotivity <jenkins@iotivity.org>
Reviewed-by: Ziran Sun <ziran.sun@samsung.com>
Reviewed-by: Dan Mihai <Daniel.Mihai@microsoft.com>