Bump version to 2.4.0

VCS plugins changes:
- SourceBitBucket 2.1.0
- SourceCgit 2.0.3
- SourceGithub 2.2.0
- SourceGitlab 2.0.3
- SourceGitphp 2.0.2
- SourceGitweb 2.0.3
- SourceSVN 2.3.0
- SourceVisualSVNServer 2.0.2

Author: dregad

Source/MantisSourceBase.class.php

@@ -19,7 +19,7 @@ abstract class MantisSourceBase extends MantisPlugin
 	 * a change in the minimum required MantisBT version: 0=1.2; 1=1.3, 2=2.x.
 	 * The framework version is incremented when the plugin's core files change.
 	 */
-	const FRAMEWORK_VERSION = '2.3.1';
+	const FRAMEWORK_VERSION = '2.4.0';
 
 	/**
 	 * Minimum required MantisBT version.