Provide branding images for CORE-V IDE

The standard set of images for Eclipse product:

• splash.bmp
• core-v_lg.png (for About)
• core-v_16.png
• core-v_32.png
• core-v_48.png
• core-v_64.png
• core-v_128.png

Would be nice to have images for launchers, but it can wait.