Added wrapper functionality

[jangroter]

This PR adds wrapper functionality to BlueSky-Gym.

Wrappers are a tool to extend the functionality of an environment, and should ideally be environment independent.
Usage of a wrapper requires initialization of the environment, and then `wrapping' this initialized environment.

See the following example for creating a simple 'noisy observation' environment

import gymnasium as gym
import bluesky_gym
from bluesky_gym.wrappers.wind import NoisyObservationWrapper
bluesky_gym.register_envs()

env = gym.make('MergeEnv-v0', render_mode='human')
noisy_env = NoisyObservationWrapper(env, noise_level=0.2)

In theory wrappers can overwrite or add functionality to all of the core functions of the environments.
Below is a more complex example utilizing the windfield wrapper to create a static windfield with 4 sources of wind and no altitude gradient:

import gymnasium as gym
import bluesky_gym
from bluesky_gym.wrappers.wind import WindFieldWrapper
import numpy as np
bluesky_gym.register_envs()

env = gym.make('MergeEnv-v0', render_mode='human')

# Define the coordinates of the wind
lat = np.array([51.9,51.9,52.1,52.1])
lon = np.array([3.9,4.1,3.9,4.1])
vnorth = np.array([[16, 12, 14, 15]]) # 2D because one dimension is used for altitude, which we leave at None
veast = np.array([[3, 7, 9, 4]])

windy_env = WindFieldWrapper(env, lat=lat, lon=lon, vnorth=vnorth, veast=veast, augment_obs=True)

[jangroter]

Main.py should not be changed in the PR, revert changes

[jangroter]

Additional check text in the readme.MD file which requires some small changes