Refactored rsync_mirror.TRsync with functional tests

CLI tools updated according with API changes
PEP8 fixes

Closes-Bug: #1570260
Closes-Bug: #1575759
Change-Id: I26b3547854d670da2da94d469f88a3ea057f07db
diff --git a/trsync/cmd/cli.py b/trsync/cmd/cli.py
index eb7fa8f..41997c9 100644
--- a/trsync/cmd/cli.py
+++ b/trsync/cmd/cli.py
@@ -46,11 +46,11 @@
                             required=False,
                             help='Specified timestamp will be used for '
                             'snapshot. Format:yyyy-mm-dd-hhMMSS')
-        parser.add_argument('--snapshot-dir',
+        parser.add_argument('--snapshots-dir', '--snapshot-dir',
                             required=False,
                             default='snapshots',
-                            help='Directory name for snapshots. "snapshots" '
-                            'by default')
+                            help='Directory name for snapshots relative '
+                            '"destination". "snapshots" by default')
         parser.add_argument('--init-directory-structure',
                             action='store_true',
                             required=False,
@@ -58,7 +58,7 @@
                             help='It specified, all directories including'
                             '"snapshots-dir" will be created on remote '
                             'location')
-        parser.add_argument('--save-latest-days',
+        parser.add_argument('--snapshot-lifetime', '--save-latest-days',
                             required=False,
                             default=61,
                             help='Snapshots for specified number of days will '
@@ -97,9 +97,9 @@
         if properties['extra'].startswith('\\'):
             properties['extra'] = properties['extra'][1:]
         properties['rsync_extra_params'] = properties.pop('extra')
-        properties['save_latest_days'] = \
-            None if properties['save_latest_days'] == 'None' \
-            else int(properties['save_latest_days'])
+        properties['snapshot_lifetime'] = \
+            None if properties['snapshot_lifetime'] == 'None' \
+            else int(properties['snapshot_lifetime'])
 
         failed = list()
         for server in servers: