### pdbaugment - join rows from one FSDB files into another

`pdbaugment` provides a different mechanism for doing FSDB file joins
than the `dbjoin` command from the base perl FSDB package.
Specifically, `pdbaugment` is designed to read a single file entirely
into memory and use it augment a second one that is read in a
streaming style.  `pdbaugment` has the advantage being faster because
it dose not need to do a full sort of both files, like `dbjoin`
requires, but has the downside of needing to store one file in memory
while performing the join.  In general, the smaller file should be
used as the *augment_file* argument, and the larger as the
`stream_file` when possible.  Matching keys in the augment file should
be unique across the file, otherwise only the second row with a give
key combination will be used.

#### Example input file 1 (*myfile.fsdb*):

```
#fsdb -F t col1 two andthree
1	key1	42.0
2	key2	123.0
3	key1	90.2
```

#### Example input file 2 (*augment.fsdb*):

```
#fsdb -F t col1 additional_column
key1	blue
key2	brown
```

#### Example command usage

```
$ pdbaugment -k two -v additional_column -- myfile.fsdb augment.fsdb
```

#### Example output

```
#fsdb -F t col1:l two:a andthree:d additional_column:a
1	key1	42.0	blue
2	key2	123.0	brown
3	key1	90.2	blue
```