remove spring-webmvc from shared, allowing tools to independently upgrade versions

before 2.7 spring-mvc was not in shared. There is not technical dependency I'm aware of that requires spring-mvc to be in shared. The normal sakai goal is less in shared not more, as that allows tool devs to pick versions themselves. If in kernel/pom.xml we simply take out the provide scope, tools will start including spring-mvc again and it won't go into shared. I've validated this doesn't cause any issues with metaobj, polls, or osp tools which are the only core tools I'm aware of that use spring-mvc.

Index: pom.xml
===================================================================
— pom.xml (revision 27929)
+++ pom.xml (revision 27930)
@@ -568,7 +568,7 @@
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>2.5.6.SEC02</version>

• <scope>provided</scope>
  + <!--scope>provided</scope-->
  </dependency>
  <dependency>
  <groupId>javax.activation</groupId>