new styles

styles/README.md

styles/basemap_bright_colorbar.png

styles/basemap_dark_colorbar.png

styles/basemap_default_colorbar.png

styles/color_palettes/basemap_blue.txt

styles/color_palettes/basemap_grey.txt

styles/color_palettes/basemap_greyblue.txt

styles/color_palettes/basemap_legacy.txt

styles/qml_layer_styles/basemap_blue.qml

styles/qml_layer_styles/basemap_grey.qml

styles/qml_layer_styles/basemap_greyblue.qml

styles/qml_layer_styles/basemap_legacy.qml

styles/qml_layer_styles/ice_sheet_glaciers.qml