Turned the way of handling upload recipe around for #370

Now I parse the recipe for environment variables and if I find the
tool.toolchain variant I replace the string.
I also created (another sigh) env var for the boards manager now with a
- between the name and the version.

Author: jantje

it.baeyens.arduino.common/src/it/baeyens/arduino/common/ConfigurationPreferences.java

@@ -102,7 +102,7 @@ public static String getBoardURLs() {
     }
 
     public static String[] getBoardURLList() {
-	return getBoardURLs().replaceAll("\r", "").split(stringSplitter);
+	return getBoardURLs().replaceAll(Const.RETURN, Const.EMPTY_STRING).split(stringSplitter);
     }
 
     public static void setBoardURLs(String urls) {

it.baeyens.arduino.common/src/it/baeyens/arduino/common/Const.java

@@ -24,7 +24,8 @@ public class Const {
 					     // to add all the time
     public static final String NEWLINE = "\n";// so I do not have //$NON-NLS-1$
 					      // to add all the time
-
+    public static final String RETURN = "\r";// so I do not have //$NON-NLS-1$
+    // to add all the time
     // General stuff
     public static final String PluginStart = "it.baeyens."; //$NON-NLS-1$
     public static final String CORE_PLUGIN_ID = PluginStart + "arduino.core"; //$NON-NLS-1$