Remove unused lowercase-comparisons from XSD

Fixes gh-3932

config/src/main/resources/org/springframework/security/config/spring-security-4.2.rnc

@@ -508,9 +508,6 @@ fsmds.attlist &=
 	use-expressions?
 fsmds.attlist &=
 	id?
-fsmds.attlist &=
-	## Compare after forcing to lowercase
-	attribute lowercase-comparisons {xsd:boolean}?
 fsmds.attlist &=
 	request-matcher?
 

config/src/main/resources/org/springframework/security/config/spring-security-4.2.xsd

@@ -1673,12 +1673,6 @@
                 </xs:documentation>
          </xs:annotation>
       </xs:attribute>
-      <xs:attribute name="lowercase-comparisons" type="xs:boolean">
-         <xs:annotation>
-            <xs:documentation>Compare after forcing to lowercase
-                </xs:documentation>
-         </xs:annotation>
-      </xs:attribute>
       <xs:attribute name="request-matcher">
          <xs:annotation>
             <xs:documentation>Defines the strategy use for matching incoming requests. Currently the options are 'mvc'

docs/manual/src/docs/asciidoc/index.adoc

@@ -8779,11 +8779,6 @@ Used to explicitly configure a FilterSecurityMetadataSource bean for use with a
 A bean identifier, used for referring to the bean elsewhere in the context.
 
 
-[[nsa-filter-security-metadata-source-lowercase-comparisons]]
-* **lowercase-comparisons**
-Compare after forcing to lower case
-
-
 [[nsa-filter-security-metadata-source-request-matcher]]
 * **request-matcher**
 Defines the strategy use for matching incoming requests. Currently the options are 'ant' (for ant path patterns), 'regex' for regular expressions and 'ciRegex' for case-insensitive regular expressions.