Update more version strings to 2.1.6

doc/base/classes.xml

@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="UTF-8" ?>
-<doc version="2.1.5.rc.custom_build" name="Engine Types">
+<doc version="2.1.6.stable.official" name="Engine Types">
 <class name="@GDScript" category="Core">
 	<brief_description>
 		Built-in GDScript functions.

misc/dist/linux/godot.6

@@ -1,4 +1,4 @@
-.TH GODOT "6" "July 2018" "godot 2.1.5-stable" "Games"
+.TH GODOT "6" "June 2019" "godot 2.1.6-stable" "Games"
 .SH NAME
 godot \- multi\-platform 2D and 3D game engine with a feature\-rich editor
 .SH SYNOPSIS

misc/dist/osx_tools.app/Contents/Info.plist

@@ -19,11 +19,11 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>2.1.5</string>
+	<string>2.1.6</string>
 	<key>CFBundleSignature</key>
 	<string>godot</string>
 	<key>CFBundleVersion</key>
-	<string>2.1.5</string>
+	<string>2.1.6</string>
 	<key>NSHumanReadableCopyright</key>
 	<string>© 2007-2019 Juan Linietsky, Ariel Manzur.</string>
 	<key>LSMinimumSystemVersion</key>