Change double quotes to single quotes

I've already done that in be69edb,
but there were still a few left.

examples/aliases.py

@@ -8,22 +8,22 @@
 
 import jack
 
-print("starting TestAlias client")
+print('starting TestAlias client')
 
 client = jack.Client('TestAlias')
 
 if client.status.server_started:
-    print("JACK server was started")
+    print('JACK server was started')
 else:
-    print("JACK server was already running")
+    print('JACK server was already running')
     if client.status.name_not_unique:
-        print("unique client name generated: {}".format(client.name))
+        print('unique client name generated: {}'.format(client.name))
 
 ports = client.get_ports()
 
-print("Testing set_alias() ...")
+print('Testing set_alias() ...')
 for i, port in enumerate(ports):
-    alias_name = "Alias Name {}".format(i)
+    alias_name = 'Alias Name {}'.format(i)
     print("port '{}' => set_alias('{}')".format(port.shortname,alias_name))
     port.set_alias(alias_name)
 
@@ -34,7 +34,7 @@
 
 print('Testing unset_alias() ...')
 for i, port in enumerate(ports):
-    alias_name = "Alias Name {}".format(i)
+    alias_name = 'Alias Name {}'.format(i)
     print("port '{}' => unset_alias('{}')".format(port.shortname,alias_name))
     port.unset_alias(alias_name)
 

jack_build.py

@@ -1,7 +1,7 @@
 from cffi import FFI
 
 ffibuilder = FFI()
-ffibuilder.set_source("_jack", None)
+ffibuilder.set_source('_jack', None)
 ffibuilder.cdef("""
 
 /* types.h */
@@ -316,5 +316,5 @@
 };
 """, packed=True)
 
-if __name__ == "__main__":
+if __name__ == '__main__':
     ffibuilder.compile(verbose=True)

src/jack.py

@@ -1751,9 +1751,9 @@ def shortname(self, shortname):
     @property
     def aliases(self):
         """Returns a list of strings with the aliases for the JACK port."""
-        ctype = "char[{}]".format(_lib.jack_port_name_size())
+        ctype = 'char[{}]'.format(_lib.jack_port_name_size())
         aliases = [_ffi.new(ctype), _ffi.new(ctype)]
-        aliasesptr = _ffi.new("char *[]", aliases)
+        aliasesptr = _ffi.new('char *[]', aliases)
         result = []
         if _lib.jack_port_get_aliases(self._ptr, aliasesptr) > 0:
             for i in 0, 1: