Changed how react panels store their options
* Added a ReactPanelPlugin as the interface that react panels export, this way react panels have clearer api, and gives us hooks to handle migrations and a way for panel to handle panel changes in the future
* Moved gauge value options into a sub oject and made editor more generic, will be moved out of gauge pane later and shared between singlestat, gauge, bargauge, honecomb
* Also remove nested options prop that was there due to bug
* Added missing Gauge props
* Fixed gauge issue that will require migration later and also value options editor did not handle null decimals or 0 decimals
* Fixed unit tests
* More fixes for react panels
* grid: fix small panels migration and make panel height closer to row height
* grid: migrate rows
* grid: increase min panel height
* grid: fix panel placement for complex layouts
* dashboard migration: refactor
* dashboard migration: add tests for grid layout
* dashboard: fix complex layout migration
* dashboard migration fix: fill current row if it possible
* test: fix karma tests by setting default panel span
* dashboard: fix migration when panel height more than row height
* dashboard: fix migration for collapsed rows
* grid: add all rows if even one collapsed or titled row is present
