etc: attempts at fixing editor highlighting for new attribute syntax

src/etc/emacs/rust-mode.el

@@ -122,7 +122,7 @@
                        ;; but the "else" or "{" should align with the beginning
                        ;; of the expression it's in.)
                        (looking-at "\\<else\\>\\|{")
-                       
+
                        (save-excursion
                          (rust-rewind-irrelevant)
                          ;; Point is now at the end of the previous ine

src/etc/gedit/share/gtksourceview-3.0/language-specs/rust.lang

@@ -282,7 +282,7 @@
     </context>
 
     <context id="attribute" style-ref="attribute" class="attribute">
-      <start extended="true">\#\[</start>
+      <start extended="true">\#!?\[</start>
       <end>\]</end>
       <include>
         <context ref="def:in-comment"/>

src/etc/kate/rust.xml

@@ -202,6 +202,7 @@
 			<RegExpr String="[0-9][0-9_]*\.[0-9_]*([eE][+-]?[0-9_]+)?(f32|f64|f)?" attribute="Number" context="#stay"/>
 			<RegExpr String="[0-9][0-9_]*&rustIntSuf;" attribute="Number" context="#stay"/>
 			<Detect2Chars char="#" char1="[" attribute="Attribute" context="Attribute" beginRegion="Attribute"/>
+			<Detect2Chars char="#" char1="!" char2="[" attribute="Attribute" context="Attribute" beginRegion="Attribute"/>
 			<RegExpr String="&rustIdent;::" attribute="Scope"/>
 			<RegExpr String="&rustIdent;!" attribute="Macro"/>
 			<RegExpr String="&apos;&rustIdent;(?!&apos;)" attribute="Lifetime"/>