Add motion commands for jumping between CriticMarkup

The ]m and [m pair normally maps to jumping between function
definitions, but as the Markdown syntax doesn't support this and the
broken attempt jumps between open and close braces anyway, overriding it
to actually recognize CriticMarkup seems like the best mapping option.

Author: alerque

autoload/criticmarkup.vim

@@ -75,8 +75,16 @@ function! criticmarkup#Critic(args)
     endif
 endfunction
 
+function! criticmarkup#JumpNext()
+	exe "normal ".v:count1."/{[-+\\~]\{2}\<CR>"
+endfunction
+
+function! criticmarkup#JumpPrevious()
+    exe "normal ".v:count1."?{[-+\\~]\{2}\<CR>"
+endfunction
+
 function! criticmarkup#CriticNext()
-    exe "normal /{[-+\\~]\\{2}\<cr>"
+	call criticmarkup#JumpNext()
     let op = input("What to do? ", "", "custom,criticmarkup#CriticCompleteFunc")
     if op =~ "accept"
         call criticmarkup#Accept()
@@ -92,3 +100,6 @@ function! criticmarkup#CriticCompleteFunc(a, c, p)
         return ""
     endif
 endfunction
+
+nmap ]m :call criticmarkup#JumpNext()<CR>
+nmap [m :call criticmarkup#JumpPrevious()<CR>