Adapt style.css for mobile devices

[fnkbsi]

For a better administration of Steve from a mobile device the style.css could use some changes.

Add differentiation between mobile devices and desktop in style.css. Add meta tag with viewport attribute to the html code. 00-charging-profile.jsp: At the removeRow button in periodsTable changed class=removeRow to id=removeRow. Add to both buttons in periodsTable the attribute class="btnScheduleRow" (use this class in css). In the snippet schedulePeriodsTable.js change the selector from class (.removeRow) to id (#removeRow)

[goekay]

hey @fnkbsi are these changes finished and stable?

[fnkbsi]

@goekay: The style looks only good on some smartphones. I can't recommend to merge this PR in master. Currently I can't work on it, so should I delete the PR or keep it as inspiration for others?