Menu item support for queryParam

[rajddesai]

Issue type

I'm submitting a ... (check one with "x")

• bug report
• feature request

Issue description

Current behavior:

Not able to pass query parms along with router link:
[queryParams]="{prop: 'xxx'}"

Expected behavior:

Would be nice to have query param support.
e.g. menuItem.queryParams
userMenu = [{ title: 'Profile', link: 'pages/profile', queryParam: "{prop: 'xxx'}" }, { title: 'Log out' }];

Steps to reproduce:

https://github.com/akveo/nebular/blob/master/src/framework/theme/components/menu/menu-item.component.html

Related code:

insert short code snippets here

Other information:

npm, node, OS, Browser

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Angular, Nebular

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