Add option for starting jack from terminal

This adds a command line option to the cadence-session-start command that would allow people to start jack from the command line as if they were pressing the start button from the cadence GUI. The new command line option is --plainstart or -ps.

Rationale: people like terminals :)

src/cadence_session_start.py

@@ -146,6 +146,13 @@ def startJack():
     if not bool(DBus.jack.IsStarted()):
         DBus.jack.StartServer()
 
+def plainStartJack():
+    DBus.bus  = dbus.SessionBus()
+    DBus.jack = DBus.bus.get_object("org.jackaudio.service", "/org/jackaudio/Controller")
+    if not bool(DBus.jack.IsStarted()):
+        startJack()
+
+
 def printLADSPA_PATH():
     EXTRA_LADSPA_DIRS = GlobalSettings.value("AudioPlugins/EXTRA_LADSPA_PATH", "", type=str).split(":")
     LADSPA_PATH_str   = ":".join(DEFAULT_LADSPA_PATH)
@@ -187,11 +194,12 @@ def printVST_PATH():
     print(VST_PATH_str)
 
 def printArguments():
-    print("\t-s|--start  \tStart session")
-    print("\t   --reset  \tForce-reset all JACK daemons and settings (disables auto-start at login)")
+    print("\t-s |--start       \tStart session (used for autostart purposes, try -ps or --plainstart instead)")
+    print("\t-ps|--plainstart  \tStart session (as if you pressed start in gui)")
+    print("\t    --reset       \tForce-reset all JACK daemons and settings (disables auto-start at login)")
     print("")
-    print("\t-h|--help   \tShow this help message")
-    print("\t-v|--version\tShow version")
+    print("\t-h |--help        \tShow this help message")
+    print("\t-v |--version     \tShow version")
 
 def printError(cmd):
     print("Invalid arguments")
@@ -234,6 +242,8 @@ if __name__ == '__main__':
             sys.exit(startSession(True, arg == "--system-start-desktop"))
         elif arg in ("-s", "--s", "-start", "--start"):
             sys.exit(startSession(False, False))
+        elif arg in ("-ps", "--ps", "-plainstart", "--plainstart"):
+            plainStartJack()
         elif arg in ("-h", "--h", "-help", "--help"):
             printHelp(cmd)
         elif arg in ("-v", "--v", "-version", "--version"):