Merge pull request #24294 from alexlyulkov:al/remove-torch7-from-dnn

Remove torch (old torch7) from dnn in 5.x #24294

Merge with https://github.com/opencv/opencv_extra/pull/1097

Completely removed torch (old torch7) from dnn:
- removed modules/dnn/src/torch directory that contained torch7 model parser
- removed readNetFromTorch() and readTorchBlob() public functions
- removed torch7 references from comments and help texts
- replaced links to t7 models by links to similar onnx models in js_style_transfer turtorial (similar to https://github.com/opencv/opencv/pull/24245/files)

samples/dnn/classification.py

@@ -16,7 +16,7 @@ def get_args_parser(func_args):
                         help='An optional path to file with preprocessing parameters.')
     parser.add_argument('--input',
                         help='Path to input image or video file. Skip this argument to capture frames from a camera.')
-    parser.add_argument('--framework', choices=['caffe', 'tensorflow', 'torch', 'darknet'],
+    parser.add_argument('--framework', choices=['caffe', 'tensorflow', 'darknet'],
                         help='Optional name of an origin framework of the model. '
                              'Detect it automatically if it does not set.')
     parser.add_argument('--std', nargs='*', type=float,