Port all? command (#365)

* Implement `From<bool>` for `Value`

* Add `All` command

* Change `IntoPipelineData` and `IntoInterruptiblePipelineData` bounds

* Refactor `PipelineIterator` impls

* Add `PipelineData::into_interruptible_iter`

* Use `into_interruptible_iter` instead of `all` helper

* Merge imports

* Refactor `PipelineData::{filter, map}`

* Change comment pronoun

* Treat `RowCondition` as a block

* Remove unnecessary braces

* Address cluppy warning

crates/nu-protocol/src/value/from.rs

@@ -1,5 +1,14 @@
 use crate::{ShellError, Span, Value};
 
+impl From<bool> for Value {
+    fn from(val: bool) -> Self {
+        Value::Bool {
+            val,
+            span: Span::unknown(),
+        }
+    }
+}
+
 impl From<u8> for Value {
     fn from(val: u8) -> Self {
         Value::Int {