Refactors git models & parsers

Adds full git status parsing
Adds git status info into status quick pick
Switches to async/await in file blame/log

src/git/models/branch.ts

@@ -0,0 +1,29 @@
+'use strict';
+
+export class GitBranch {
+
+    current: boolean;
+    name: string;
+    remote: boolean;
+
+    constructor(branch: string) {
+        branch = branch.trim();
+
+        if (branch.startsWith('* ')) {
+            branch = branch.substring(2);
+            this.current = true;
+        }
+
+        if (branch.startsWith('remotes/')) {
+            branch = branch.substring(8);
+            this.remote = true;
+        }
+
+        const index = branch.indexOf(' ');
+        if (index !== -1) {
+            branch = branch.substring(0, index);
+        }
+
+        this.name = branch;
+    }
+}