Add solidgauge option for highcharts

Adding a patch which adds solidgauge as chart type for 5.0.x-dev.

The last submitted patch, 11: Add_solidgauge_option_for_highcharts-3305105-11.patch, failed testing. View results →
- codesniffer_fixes.patch Interdiff of automated coding standards fixes only.

Fixing test issues which are related to stops schema structure.

The last submitted patch, 13: Add_solidgauge_option_for_highcharts-13.patch, failed testing. View results →
- codesniffer_fixes.patch Interdiff of automated coding standards fixes only.

Trying still to fix the same failing test related to schema.

The last submitted patch, 15: Add_solidgauge_option_for_highcharts-3305105-15.patch, failed testing. View results →
- codesniffer_fixes.patch Interdiff of automated coding standards fixes only.

Standard issue fixes.