You can use the pre-distributed NoFormatting Paste plugin to paste text without formatting. To set up the Win+V shortcut combination, you will have to use ClipjumpCustom.ini. Here is an example code -

[paste_without_formatting]
bind = Win+v
run  = API.runPlugin(noformatting_paste.ahk)

Now pressing Win+V will paste the current clipboard trimming any formatting. If it doesn't work, make sure you have restarted Clipjump.

Trimming the Whitespace

The updated version of NoFormatting Paste allows trimming whitespace from the start and end of the string. It was released after Clipjump v11.6 (07/08/14). In case you don't have NoFormatting Paste version 0.2, download it from GitHub. After downloading and setting it up, you will have to pass 1 as the first parameter of the plugin to trim all whitespaces. Example -

[paste_without_formatting]
bind = Win+v
run  = API.runPlugin(noformatting_paste.ahk, 1)

The same feature is available in Common Formats as `TrimWhiteSpaces` but that's a different thing. :-)