Fix signed/unsigned comparison warnings, fix cpdef warning

Author: taras

uvloop/handles/pipe.pxd

@@ -25,6 +25,8 @@ cdef class ReadUnixTransport(UVStream):
     cdef ReadUnixTransport new(Loop loop, object protocol, Server server,
                                object waiter)
 
+    cpdef write(self, data)
+
 
 cdef class WriteUnixTransport(UVStream):
 

uvloop/handles/pipe.pyx

@@ -156,7 +156,7 @@ cdef class ReadUnixTransport(UVStream):
     def get_write_buffer_size(self):
         raise NotImplementedError
 
-    def write(self, data):
+    cpdef write(self, data):
         raise NotImplementedError
 
     def writelines(self, list_of_data):

uvloop/sslproto.pxd

@@ -67,13 +67,13 @@ cdef class SSLProtocol:
         bint _ssl_writing_paused
         bint _app_reading_paused
 
-        size_t _incoming_high_water
-        size_t _incoming_low_water
+        Py_ssize_t _incoming_high_water
+        Py_ssize_t _incoming_low_water
         bint _ssl_reading_paused
 
         bint _app_writing_paused
-        size_t _outgoing_high_water
-        size_t _outgoing_low_water
+        Py_ssize_t _outgoing_high_water
+        Py_ssize_t _outgoing_low_water
 
         object _app_protocol
         bint _app_protocol_is_buffer