Update submodule vim/bundle/open-browser e32748d...a604c0d

* vim/bundle/open-browser e32748d...a604c0d (29):
  > applied @itchyny patch (ref: #15)
  > '\<' is not good because it is affected by 'iskeyword' (ref: #15)
  > fix #15: reuse concealed line, not getline('.') (thanks @itchyny for pointing me out)
  > close #15, close #5: ignore concealed characters (thanks @chikatoike)
  > fix #22: '\>' is affected by 'iskeyword' (great thanks for @ynkdir)
  > Merge branch 'change-browser-commands-default'
  > fix comment in the previous change
  > escape '!' also for ':!start' (thanks @basyura)
  > fix URL regexp a bit in s:get_url_on_cursor() (ref: #22)
  > Merge pull request #21 from yoshikaw/master
  > fix: main code in s:open_browser() was incorrectly reverted at d380049
  > fix doc for g:openbrowser_browser_commands
  > Merge branch 'option-browser-commands'
  > ready for a merge into master
  > move all global variables to plugin/openbrowser.vim (ref: #20)
  > Merge pull request #20 from inkarkat/allow-no-default-search-engines
  > s:system(...) -> s:system({expr})
  > remove g:openbrowser_{isfname,iskeyword} also from a doc
  > fix s:detect_query_type(): just return s:seems_{path,uri}() results
  > escape cmdline-special characters again
  > remove g:openbrowser_{isfname,iskeyword} because they were no longer used
  > remove codes setting a value to $OPENBROWSER_URI
  > fix #11: extract URL under cursor like vim-textobj-url
  > openbrowser#search(): skip blank string
  > use s:get_url_on_cursor() not expand('<cword>')
  > deprecate vimproc support
  > fix #18: use :!start on MS Windows
  > openbrowser#shellescape(): support other than MS Windows
  > do escape only when a:uri contains special characters