Expand error message upon -style arg parse error

When the user adds invalid arguments to the -style switch of
clang-format, the error message may yield different responses depending
on the type of failure.

Expand error message given to the user to not only be verbose on 'key'
errors.

An example:

    let g:clang_format#style_options = { "Standard" : "go" }

Will result in:

    Error detected while processing function clang_format#replace[6]..<SNR>77_error_message:
    line    1:
    clang-format has failed to format.
    YAML:1:63: error: unknown enumerated scalar
    {BasedOnStyle: LLVM, IndentWidth: 4, UseTab: false, Standard: 'go'}
                                                                  ^~~~
    Error parsing -style: Invalid argument

Author: Kypert

autoload/clang_format.vim

@@ -89,9 +89,9 @@ endfunction
 
 function! s:error_message(result) abort
     echoerr 'clang-format has failed to format.'
-    if a:result =~# '^YAML:\d\+:\d\+: error: unknown key '
+    if a:result =~# '^YAML:\d\+:\d\+: error: '
         echohl ErrorMsg
-        for l in split(a:result, "\n")[0:1]
+        for l in split(a:result, "\n")
             echomsg l
         endfor
         echohl None