Skip go-style backtick-quoted strings

Fixes #28

plugin/sleuth.vim

@@ -14,6 +14,7 @@ function! s:guess(lines) abort
   let ccomment = 0
   let podcomment = 0
   let triplequote = 0
+  let backtick = 0
 
   for line in a:lines
 
@@ -50,6 +51,15 @@ function! s:guess(lines) abort
       let triplequote = 1
     endif
 
+    if backtick
+      if line =~# '^[^`]*`[^`]*$'
+        let backtick = 0
+      endif
+      continue
+    elseif line =~# '^[^`]*`[^`]*$'
+      let backtick = 1
+    endif
+
     let softtab = repeat(' ', 8)
     if line =~# '^\t'
       let heuristics.hard += 1