Bump version to 2.2-alpha

There are now new developments that will not be in 2.1-stable

tools/Godot.app/Contents/Info.plist

@@ -19,11 +19,11 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.1-dev</string>
+	<string>2.2-dev</string>
 	<key>CFBundleSignature</key>
 	<string>godot</string>
 	<key>CFBundleVersion</key>
-	<string>2.1-dev</string>
+	<string>2.2-dev</string>
 	<key>NSHumanReadableCopyright</key>
 	<string>© 2007-2016 Juan Linietsky, Ariel Manzur</string>
 	<key>LSMinimumSystemVersion</key>

version.py

@@ -1,5 +1,5 @@
 short_name="godot"
 name="Godot Engine"
 major=2
-minor=1
-status="rc1"
+minor=2
+status="alpha"