Enables the launcher to cache output

[Nanguage]

1. Cache the launcher function's output
2. Cache the file output: check if specified output file are exist, and only start the job when file not exist.

Example:

@launcher(cache='disk')
def add(a, b):
    return a + b

res = add(1, 2)  # will start job
res = add(1, 2)  # will directly load result from cache

# cache file output
from executor.engine.launcher import file_output

@launcher(cache='disk')
@file_output('{name}.txt')
def generate_hellos(name: str, times: int):
    with open(name + '.txt', 'w') as f:
        for _ in range(times):
            f.write(f"Hello {name}\n")

generate_hellos('Tom', 10)  # will start job
generate_hellos('Tom', 10)  # will not start job
generate_hellos('Mike', 10) # will start job