EEL DSL for a CLI shell

EEL DSL for a CLI shell

- A Scala DSL for EEL commands.
- The Scala REPL to be used as an interactive shell
- Scala variables, loops and conditional statements can be combined with DSL commands to easily script tasks
- A bootstrap shell script called *eel-shell* similar to *spark-shell* - will automatically import the eel DSL packages
- Also automatically import OS packages to allow for OS commands to be run and combined with the DSL

*Import*

Import data with options from an EEL source to a sink

import from jdbc
with driver=blah,url=blah,sql=blah
to hive
with db=blah,table=blah

Import from jdbc
with driver=blah,url=blah,sql=blah
to Parquet
with path=blah

*Export*

Export data with options to an EEL sink from a source

export to hive
with db=blah,table=blah
from jdbc
with driver=blah,url=blah,sql=blah

export to hive
with db=blah,table=blah
from Parquet
with path=blah

- Note allow a *transform* sub-command at the appropriate place to do custom transformations on the underlying rows in the frame.

More commands to follow....

Look for existing CLI or shell-related code in the repository, possibly under src/main/scala/com/fiftyzero/eel. Check for any existing DSL implementations or REPL integration. The bootstrap script 'eel-shell' would need to be created, likely in a scripts/ directory. Understanding the EEL SDK's core data import/export commands is essential before designing the DSL syntax and integration with Scala REPL.

Written by the indexing model from the issue text.