move dataframe commands to nu-cmd-dataframe (#9241)

All of the dataframe commands ported over with no issues...

### 11 tests are commented out (for now)

So 100 of the original 111 tests are passing with only 11 tests being
ignored for now..

As per our conversation in the core team meeting on Wednesday
I took @jntrnr  suggestion and just commented out the tests dealing
with
[IntoDatetime](https://github.com/nushell/nushell/blob/main/crates/nu-command/src/conversions/into/mod.rs)

Later on we can move this functionality out of nu-command if we decide
it makes sense...

### The following tests were ignored...

```rust
modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_day.rs
modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_hour.rs
modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_minute.rs

modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_month.rs
modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_nanosecond.rs
modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_ordinal.rs

modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_second.rs
modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_week.rs
modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_weekday.rs

modified:   crates/nu-cmd-dataframe/src/dataframe/series/date/get_year.rs
modified:   crates/nu-cmd-dataframe/src/dataframe/series/string/strftime.rs
```

crates/nu-cmd-dataframe/src/dataframe/eager/get.rs

@@ -0,0 +1,92 @@
+use nu_engine::CallExt;
+use nu_protocol::{
+    ast::Call,
+    engine::{Command, EngineState, Stack},
+    Category, Example, PipelineData, ShellError, Signature, Span, SyntaxShape, Type, Value,
+};
+
+use crate::dataframe::values::utils::convert_columns_string;
+
+use super::super::values::{Column, NuDataFrame};
+
+#[derive(Clone)]
+pub struct GetDF;
+
+impl Command for GetDF {
+    fn name(&self) -> &str {
+        "dfr get"
+    }
+
+    fn usage(&self) -> &str {
+        "Creates dataframe with the selected columns."
+    }
+
+    fn signature(&self) -> Signature {
+        Signature::build(self.name())
+            .rest("rest", SyntaxShape::Any, "column names to sort dataframe")
+            .input_type(Type::Custom("dataframe".into()))
+            .output_type(Type::Custom("dataframe".into()))
+            .category(Category::Custom("dataframe".into()))
+    }
+
+    fn examples(&self) -> Vec<Example> {
+        vec![Example {
+            description: "Returns the selected column",
+            example: "[[a b]; [1 2] [3 4]] | dfr into-df | dfr get a",
+            result: Some(
+                NuDataFrame::try_from_columns(vec![Column::new(
+                    "a".to_string(),
+                    vec![Value::test_int(1), Value::test_int(3)],
+                )])
+                .expect("simple df for test should not fail")
+                .into_value(Span::test_data()),
+            ),
+        }]
+    }
+
+    fn run(
+        &self,
+        engine_state: &EngineState,
+        stack: &mut Stack,
+        call: &Call,
+        input: PipelineData,
+    ) -> Result<PipelineData, ShellError> {
+        command(engine_state, stack, call, input)
+    }
+}
+
+fn command(
+    engine_state: &EngineState,
+    stack: &mut Stack,
+    call: &Call,
+    input: PipelineData,
+) -> Result<PipelineData, ShellError> {
+    let columns: Vec<Value> = call.rest(engine_state, stack, 0)?;
+    let (col_string, col_span) = convert_columns_string(columns, call.head)?;
+
+    let df = NuDataFrame::try_from_pipeline(input, call.head)?;
+
+    df.as_ref()
+        .select(col_string)
+        .map_err(|e| {
+            ShellError::GenericError(
+                "Error selecting columns".into(),
+                e.to_string(),
+                Some(col_span),
+                None,
+                Vec::new(),
+            )
+        })
+        .map(|df| PipelineData::Value(NuDataFrame::dataframe_into_value(df, call.head), None))
+}
+
+#[cfg(test)]
+mod test {
+    use super::super::super::test_dataframe::test_dataframe;
+    use super::*;
+
+    #[test]
+    fn test_examples() {
+        test_dataframe(vec![Box::new(GetDF {})])
+    }
+}