added substitutions

src/substitutions.rs

@@ -0,0 +1,23 @@
+use chrono::{DateTime, Utc};
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "PascalCase")]
+pub struct Substitutions {
+    pub from: DateTime<Utc>,
+    pub to: DateTime<Utc>,
+    pub changes: Vec<SubstitutionChange>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(rename_all = "PascalCase")]
+pub struct SubstitutionChange {
+    pub change_subject: Option<String>, //Unknown if string is the right type
+    pub day: DateTime<Utc>,
+    pub hours: String,
+    pub change_type: String,
+    pub description: String,
+    pub time: String,
+    pub type_abbrev: Option<String>, //Unknown if string is the right type,
+    pub type_name: Option<String>,   //Unknown if string is the right type
+}