A Twitter to Mastodon copy bot written in Rust

It:
* copies the content (text) of the original Tweet
* dereferences the links
* gets every attached media (photo, video or gif)

If any of the last steps failed, the Toot gets published with the exact same text as the Tweet.

RT are excluded, replies are included.but only the source threads are copied, not the actual replies to other Twitter users.

# Usage

First up, create a configuration file (default path is `/usr/local/etc/scootaloo.toml`). It will look like this:

```
[scootaloo]

last_tweet_path="/usr/local/etc/last_tweet" ## file containing the last tweet id received, must be writable
cache_path="/tmp/scootaloo" ## a dir where the temporary files will be download, must be writeable

[twitter]
username="NintendojoFR" ## User Timeline to copy

## Consumer/Access key for Twitter (can be generated at https://developer.twitter.com/en/apps)
consumer_key="MYCONSUMERKEY"
consumer_secret="MYCONSUMERSECRET"
access_key="MYACCESSKEY"
access_secret="MYACCESSSECRET"
```

Then run the command with the `register` subcommand:
```
scootaloo register --host https://m.nintendojo.fr
```

This will give you the end of the TOML file. It will look like this:

```
[mastodon]
base = "https://m.nintendojo.fr"
client_id = "MYCLIENTID"
client_secret = "MYCLIENTSECRET"
redirect = "urn:ietf:wg:oauth:2.0:oob"
token = "MYTOKEN"
```

You can then run the application via `cron` for example. Here is the generic usage:

```
USAGE:
    scootaloo [OPTIONS] [SUBCOMMAND]

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -c, --config <CONFIG_FILE>    TOML config file for scootaloo (default /usr/local/etc/scootaloo.toml)

SUBCOMMANDS:
    help        Prints this message or the help of the given subcommand(s)
    register    Command to register to a Mastodon Instance
```

# Quirks

Scootaloo does not respect the spam limits imposed by Mastodon: it will make a 429 error if too much Tweets are converted to Toots in a short amount of time (and it will not recover from it). By default, it gets the last 200 tweets from the user timeline (which is a lot!). It is recommended to put a Tweet number into the `last_tweet` file before copying an old account.

You can do that with a command like:
```
echo -n '8189881949849' > last_tweet
```

**This file should only contain the last tweet ID without any other char (no EOL or new line).**