Refactoring v1.0 prep

This is the first big refactoring step towards v1.0 Lots of functions changed places and names, so there are probably lots of bugs to correct now.

docs/notebooks/blob_detection.ipynb

 %% Cell type:code id: tags:
 
 ``` python
 import qim3d
 ```
 
 %% Cell type:markdown id: tags:
 
 ### Blob detection notebook
 
 %% Cell type:markdown id: tags:
 
 This notebook shows how to do **blob detection** in a 3D volume using the `qim3d` library.
 
 Blob detection is done by using the `qim3d.processing.blob_detection` method, which detects blobs by using the Difference of Gaussian (DoG) blob detection method, and returns two arrays:
 - `blobs`: The blobs found in the volume stored as `(p, r, c, radius)`
 - `binary_volume`: A binary mask of the volume with the blobs marked as `True`
 
 %% Cell type:markdown id: tags:
 
 ### **Example 1**: Blob detection in cement volume
 
 %% Cell type:markdown id: tags:
 
 **Applying Gaussian filter to volume**
 
 %% Cell type:code id: tags:
 
 ``` python
 # Import 3D volume of cement
 cement = qim3d.examples.cement_128x128x128
 
 # Visualize slices of the original cement volume
-qim3d.viz.slices(cement, n_slices = 5, show = True)
+qim3d.viz.slices_grid(cement, n_slices = 5, show = True)
 
 # Apply Gaussian filter to the cement volume
 cement_filtered = qim3d.processing.gaussian(cement, sigma = 2)
 
 # Visualize slices of the filtered cement volume
-qim3d.viz.slices(cement_filtered)
+qim3d.viz.slices_grid(cement_filtered)
 ```
 
 %% Output
 
 
     <Figure size 1000x200 with 5 Axes>
 
 %% Cell type:markdown id: tags:
 
 **Detecting blobs in volume**
 
 %% Cell type:code id: tags:
 
 ``` python
 # Detect blobs, and get binary mask
 blobs, mask = qim3d.processing.blob_detection(
     cement_filtered,
     min_sigma=1,
     max_sigma=8,
     threshold=0.001,
     overlap=0.1,
     background="bright"
     )
 
 # Number of blobs found
 print(f'Number of blobs found in the volume: {len(blobs)} blobs')
 ```
 
 %% Output
 
     Bright background selected, volume will be inverted.
 
     Number of blobs found in the volume: 1813 blobs
 
 %% Cell type:code id: tags:
 
 ``` python
 # Visualize blobs on slices of cement volume
 qim3d.viz.detection.circles(blobs, cement, alpha = 0.8, show = True, color = 'red')
 ```
 
 %% Output
 
     interactive(children=(IntSlider(value=64, description='Slice', max=127), Output()), layout=Layout(align_items=…
 
 %% Cell type:markdown id: tags:
 
 **Binary mask of detected blobs**
 
 %% Cell type:code id: tags:
 
 ``` python
 # Visualize binary mask
 qim3d.viz.slicer(mask)
 ```
 
 %% Output
 
     interactive(children=(IntSlider(value=64, description='Slice', max=127), Output()), layout=Layout(align_items=…