The `boto` library (long ago superseded by `boto3`) has not had an official
release in over two years or even a commit in the last 18 months. Importing
the package (or indirectly importing it by via `moto`) generates a deprecation
warning. Additionally, an ever-increasing number of `moto` users who have
left `boto` behind for `boto3` are still being forced to install `boto`.
This commit vendors a very small subset of the `boto` library--only the code
required by `moto` to run--into the /packages subdirectory. A README file
is included explaining the origin of the files and a recommendation for how
they can be removed entirely in a future release.
NOTE: Users of `boto` will still be able to use `moto` after this is merged.
closes#2978closes#3013closes#3170closes#3418
relates to #2950
