Change SQL completion icon

[sunix]

using icon stevan will provide

[mleduque]

Can't use SVG in completion.
Temporary workaround : use export to PNG

[mleduque]

Waits for https://jira.codenvycorp.com/browse/IDEX-658 .

[mleduque]

There is still a fill color issue, need to check if its on our side or if it's on IDE side.