Add reproject method to AreaDefinition

Feature Request

Is your feature request related to a problem? Please describe.
Sometimes I just want to reproject an AreaDefinition e.g. use a different projection but keep the extent and also use a resolution "close" to the source AreaDefinition. Even with all the helpers for creating AreaDefinitions this
is a little cumbersome and takes to much time especially if this is just needed "on-the-fly" (meaning not worth putting it into a yaml file to keep it around).

Describe the solution you'd like
It would be nice to have a reproject method which produces a new AreaDefinition with the given projection.
For use in our working group I created the following some time ago:

import pyproj
from pyresample import geometry
from pyresample.utils.proj4 import proj4_dict_to_str

def reproject_area(area, target_proj):
    """
    Reprojects area to target projection
    
    Createa a new area definition in the target projection
    while keeping the geographic extent and spatial resolution
    of the source area.
    
    Parameters
    ----------
    area : pyresample area definition
    target_proj : proj dict
    
    Returns
    -------
    area
    
    Todo
    ----
    - handling of area definitions based solely on lat/lon
      e.g. swath areas
    - allow other inputs for target_proj than proj4 dicts
    
    """
    if type(area) == geometry.SwathDefinition:
        return NotImplementedError("Areas of type swath are currently not supported!")
    
    area_id = area.area_id
    area_desc = area.name
    pcs_id = target_proj["proj"]
    
    target_crs = pyproj.CRS.from_proj4(proj4_dict_to_str(target_proj))
    
    xmax, ymax, xmin, ymin = area.area_extent
        
    transformer = pyproj.Transformer.from_crs(area.crs, target_crs, always_xy=True)
    xx, yy = transformer.transform([xmin, xmax], [ymin, ymax])
    target_extent = [xx[0], yy[0], xx[1], yy[1]]
    
    area_res_x = (xmax - xmin) / area.x_size
    area_res_y = (ymax - ymin) / area.y_size
    
    target_size_x = abs(int((target_extent[2] - target_extent[0]) / area_res_x))
    target_size_y = abs(int((target_extent[3] - target_extent[1]) / area_res_y))
        
    return geometry.AreaDefinition(area_id, area_desc, pcs_id, target_proj, target_size_x, target_size_y, target_extent)

This currently does not support swath areas and it would be nice to accept other projection formats than proj4 dicts. Also depending on the source area projection handling of the resolution calculation might need some refinement.

Describe any changes to existing user workflow
None.

Locate AreaDefinition in pyresample.geometry and compare it with the supplied reproject_area example; inspect existing CRS, extent, and resolution handling first. Define completion around a method that creates a new AreaDefinition for another projection while preserving the source extent and resolution intent, and account for the noted swath and projection-input cases.