Cleanup the helper scripts

* Remove from __future__ import print_function, because we
  no longer support Python2.
* Clean out unused parts of tools/scripts/scriptCommon.py
* Move appveyorMergeCoverageScript to Python3
* Update user reporting in *release scripts
* Cleanup module imports

tools/scripts/scriptCommon.py

@@ -1,31 +1,4 @@
 import os
 import sys
-import subprocess
-
 
 catchPath = os.path.dirname(os.path.dirname(os.path.realpath( os.path.dirname(sys.argv[0]))))
-
-def getBuildExecutable():
-    if os.name == 'nt':
-        dir = os.environ.get('CATCH_DEV_OUT_DIR', "cmake-build-debug/projects/SelfTest.exe")
-        return dir
-    else:
-        dir = os.environ.get('CATCH_DEV_OUT_DIR', "cmake-build-debug/projects/SelfTest")
-        return dir
-
-
-def runAndCapture( args ):
-    child = subprocess.Popen(" ".join( args ), shell=True, stdout=subprocess.PIPE)
-    lines = []
-    line = ""
-    while True:
-        out = child.stdout.read(1)
-        if out == '' and child.poll():
-            break
-        if out != '':
-            if out == '\n':
-                lines.append( line )
-                line = ""
-            else:
-                line = line + out
-    return lines