Task: xts alias recursive option

[TB-1993]

Goal

To allow adding all .xts files found in the tree, below the specified directory, without requiring multiple runs of the app.

This can be done using a --recursive|-r option with alias. The user would specify the path directory and all the .xts files found within the directory and it's subdirectory would be added to the users list of aliases.
For example, the tree shown below would add the following aliases:
xts alias ./test-xts/ --recursive

test-xts
├── subdir1
│  ├── test1.xts
│  └── test2.xts
├── subdir2
│  └── newtest.xts
└── test1.xts

Aliases:

test-xts/test1 -> ./test-xts/test1.xts
test-xts/subdir1/test1 -> ./test-xts/subdir1/test1.xts
test-xts/subdir1/test2 -> ./test-xts/subdir1/test2.xts
test-xts/subdir2/newtest -> ./test-xts/subdir2/newtest.xts

Notes (Optional)

No response