Ngx-datatable: Allow user to keep aspects of default footer in a customer footer template.

[jguttman94]

[ ] bug report => search github for a similar issue or PR before submitting
[ X ] feature request
[ ] support request => Please do not submit support request here, post on Stackoverflow or Gitter
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Current behavior
The use of the new custom footer template allows the user to display the information they want in the foot of their datatable. This overrides the default footer with the user's custom defined one.

Expected behavior
Allow the user to keep certain elements of the default footer, but add their own values as well.

Reproduction of the problem
The working demo, http://swimlane.github.io/ngx-datatable/#, currently displays the custom footer template.

What is the motivation / use case for changing the behavior?
What I specifically would like to see is an additional element on the default footer called 'Set Row Limit' that allows the user to determine how many rows to bring back. By using the custom template and adding that feature in, the pagination aspect of the default footer is removed. Allow the user to keep the pagination component of the default footer if they choose.

Please tell us about your environment:
WebStorm IDE

• Table version: 8.2.1

• Angular version: 4.0.0

• Browser: [all | Chrome XX | Firefox XX | IE XX | Safari XX | Mobile Chrome XX | Android X.X Web Browser | iOS XX Safari | iOS XX UIWebView | iOS XX WKWebView ]

Chrome, Internet Explorer, Firefox

• Language: [all | TypeScript X.X | ES6/7 | ES5]
  HTML, TypeScript 2.2.0

[timwright35]

Yea, the pagination missing is definitely an issue when using a custom footer, the main reason I was looking into a second "summary row" instead of in the footer itself.

[amcdnl]

The footer is not exported so you can use it now :)

[nssantos]

How can I use without overriding the default footer?