Merge pull request #132 from itchyny/master

Remove duplicated command in the history
Use uniq in histories
Revert "Use uniq in histories"

This reverts commit 665f8621885db3ad30396a584d23b79b8dbabf70.
Improve unite sources
Fix #133 add vexe insert option
Fix #134 manual complete problem
Add marker
Fix #138 g:vimshell_interactive_update_time behavior
Remove autodate
Fix start history complete error
Fix vimshell_data_directory problem
Add <Plug>(vimshell_interrupt)
Change default mappings
Fix vimshell/external_history source
Fix for latest Vim specification
Fix startinsert! problem
Fix #225 improve disable completion
Improve completion behavior
Fix completion problem
Improve disable_auto_complete.