[Libfix] Remove rpyc_get_connection() dependency from code

Problem:
`g.rpyc_get_connection()` has a limitaion where it can't
convert python2 calls to python3 calls. Due to this a large
number of testcases fail when executed from a python2 machine
on a python3 only setup or visa versa with the below stack trace:
```
E  ========= Remote Traceback (1) =========
E  Traceback (most recent call last):
E  File "/root/tmp.tL8Eqx7d8l/rpyc/core/protocol.py", line 323, in _dispatch_request
E       res = self._HANDLERS[handler](self, *args)
E  File "/root/tmp.tL8Eqx7d8l/rpyc/core/protocol.py", line 591, in _handle_inspect
E       if hasattr(self._local_objects[id_pack], '____conn__'):
E  File "/root/tmp.tL8Eqx7d8l/rpyc/lib/colls.py", line 110, in __getitem__
E       return self._dict[key][0]
E  KeyError: (b'rpyc.core.service.SlaveService', 94282642994712, 140067150858560)
```

Solution:
The solution here is to modify the code to not use
`g.rpyc_get_connection()`. The following changes are done
to accomplish it:
1)Remove code which uses g.rpyc_get_connection() and use generic
logic in functions:
 a. do_bricks_exist_in_shd_volfile()
 b. get_disk_usage()
 c. mount_volume()
 d. list_files()
 f. append_string_to_file()
2)Create files which can be uploaded and executed on
clients/servers to avoid rpc calls in functions:
 a. calculate_hash()
 b. validate_files_in_dir()
3)Modify setup.py to push the below files to
`/usr/share/glustolibs/scripts/`:
 a.compute_hash.py
 b.walk_dir.py

Change-Id: I00a81a88382bf3f8b366753eebdb2999260788ca
Signed-off-by: kshithijiyer <kshithij.ki@gmail.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/glustolibs-gluster/setup.py b/glustolibs-gluster/setup.py
index b3f9cb09c..05e59fde6 100644
--- a/glustolibs-gluster/setup.py
+++ b/glustolibs-gluster/setup.py
@@ -1,5 +1,5 @@
 #!/usr/bin/env python
-# Copyright (c) 2016-2019 Red Hat, Inc.
+# Copyright (c) 2016-2020 Red Hat, Inc.
 #
 # This program is free software; you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -49,6 +49,8 @@ setup(
 )
 
 try:
-    dir_util.copy_tree('./gdeploy_configs', '/usr/share/glustolibs/gdeploy_configs')
+    for srcdir, destdir in (('./gdeploy_configs', '/usr/share/glustolibs/gdeploy_configs'),
+                            ('./scripts', '/usr/share/glustolibs/scripts/')):
+        dir_util.copy_tree(srcdir, destdir)
 except:
     pass