In dynamic.properties, replace backslashes with forward slashes - this allows Windows style classpaths (e.g., C:\foo\bar) to be replaced with forward slashes and to be correctly included. Fixes issue 4048.

Change-Id: I2258371daf85f11ae5559d9a4f26891d70fcf491
Reviewed-on: http://gerrit.dmdirc.com/1156
Reviewed-by: Chris Smith <chris@dmdirc.com>
Automatic-Compile: DMDirc Local Commits <dmdirc@googlemail.com>

nbproject/build-impl.xml

@@ -44,6 +44,7 @@ is divided into following sections:
 </echo>
         <echo file="nbproject/private/dynamic.properties" append="true">private.classpath=${toString:plugins.libs}
 </echo>
+        <replace file="nbproject/private/dynamic.properties" token="\" value="/"/> <!-- this replaces backslashes with slashes on Windows -->
         <property file="nbproject/private/dynamic.properties"/>
     </target>
     <target depends="-pre-init,-init-private" name="-init-user">