Only load vendored jQuery on NC34+, verified against NC32/33/34 in testbak/

Core still provides a working jQuery on NC32/33, but via a read-only
window.$ getter - loading our own vendored copy there too made its UMD
wrapper throw trying to reassign window.$ (confirmed on real containers,
harmless in practice since this app attaches via window.jQuery, but a real
avoidable console exception). Gate the extra script() call on
ServerVersion::getMajorVersion() >= 34 instead.

Re-tested both sides of the boundary: NC32 no longer requests jquery.js and
has zero console errors; NC34 still requests it and still works.

appinfo/info.xml

@@ -5,7 +5,7 @@
     <name>Extended OCC Web</name>
     <summary>OCC Commands in a web terminal</summary>
     <description><![CDATA[Run OCC Commands in a web terminal]]></description>
-    <version>0.4.2</version>
+    <version>0.4.3</version>
     <licence>agpl</licence>
     <author mail="dillard.blom@ensembia.com" >Dillard Blom</author>
     <namespace>OCCWeb</namespace>