Rename commit method to include create prefix

Author: mattt

Sources/Git/Repository.swift

@@ -193,7 +193,7 @@ public final class Repository {
     }
 
     @discardableResult
-    public func commit(message: String, author: Signature? = nil, committer: Signature? = nil) throws -> Commit {
+    public func createCommit(message: String, author: Signature? = nil, committer: Signature? = nil) throws -> Commit {
         let tree = try lookup(try Object.ID { oid in
             try attempt { git_index_write_tree(oid, index?.pointer) }
         }) as Tree?

Tests/GitTests/GitTests.swift

@@ -84,7 +84,7 @@ final class GitTests: XCTestCase {
         try repository.add(paths: ["hello.txt"])
 
         let signature = try Signature(name: "Mona Lisa Octocat", email: "mona@github.com")
-        let commit = try repository.commit(message: "Initial commit", author: signature, committer: signature)
+        let commit = try repository.createCommit(message: "Initial commit", author: signature, committer: signature)
 
         XCTAssertEqual(repository.head?.commit, commit)
         XCTAssertEqual(commit.message, "Initial commit")