fix transposed defaults in showmode and shell help

vimperator/locale/en-US/options.txt

@@ -614,7 +614,7 @@ ____
 
 
 |\'shell'| |\'sh'|
-||'shell' 'sh'|| string (default: on)
+||'shell' 'sh'|| string (default: "-c", Win32: "/c")
 ____
 Shell to use for executing :! and :run commands.
 ____
@@ -630,7 +630,7 @@ ____
 
 
 |\'nosmd'| |\'noshowmode'| |\'smd'| |\'showmode'|
-||'showmode' 'smd'|| boolean (default: "-c", Win32: "/c")
+||'showmode' 'smd'|| boolean (default: on)
 ____
 Show the current mode in the command-line.
 ____