add igors mask svgs, add composer clear_color pref, remove key DEL for mask gui, add clear_color to vframe, colorBoxBtn tweaks
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_all_linear.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_all_smooth.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_button_dn.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_button_hi.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_button_up.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_crv_linear.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_crv_smooth.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_pnt_linear.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_pnt_smooth.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_prst_crc.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_prst_load.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_prst_ovl.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_prst_save.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_prst_sqr.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_prst_trash.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_prst_tri.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_pstn_cen.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_pstn_nrm.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_chkd.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_chkdhi.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_up.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_uphi.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_x.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_xdown.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_xy.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_xydown.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_y.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/mask_scale_ydown.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/unclear.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/unclear_dn.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/unclear_hi.svg
- [DH] cinelerra-5.1/plugins/theme_cakewalk/source_SVG/unclear_up.svg