feat: add convert_to_delta (delta-io#1686)

# Description
Add a convert_to_delta operation for converting a Parquet table to a
Delta Table in place.

# Related Issue(s)
- closes delta-io#1041
- closes delta-io#1682
<!---
For example:

- closes delta-io#106
--->

# Documentation

<!---
Share links to useful documentation
--->

crates/deltalake-core/src/kernel/schema.rs

@@ -1,6 +1,8 @@
 //! Delta table schema
 
+use std::borrow::Borrow;
 use std::fmt::Formatter;
+use std::hash::{Hash, Hasher};
 use std::sync::Arc;
 use std::{collections::HashMap, fmt::Display};
 
@@ -110,6 +112,20 @@ pub struct StructField {
     pub metadata: HashMap<String, MetadataValue>,
 }
 
+impl Hash for StructField {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.name.hash(state);
+    }
+}
+
+impl Borrow<str> for StructField {
+    fn borrow(&self) -> &str {
+        self.name.as_ref()
+    }
+}
+
+impl Eq for StructField {}
+
 impl StructField {
     /// Creates a new field
     pub fn new(name: impl Into<String>, data_type: DataType, nullable: bool) -> Self {