`gl.shaderSource` is disruptive and doesn't provide enough information

[JannikGM]

I have a long (generated) shader and it fails to compile. I'd like to review the shader source. Some observations:

• shaderSource in Spector.js is very long and it's easy to miss other commands inbetween 2 shaderSource which are huge blocks. The shaderSource log entry should be more minimalistic and show less information.
• The actual argument to shaderSource is not shown in the log, it's trimmed by "..." so I can't see the complete shader. Ideally, I'd like to open it in the shader editor, just like a shader during draw operations.
• The actual argument to shaderSource is not shown in the sidebar "Command Arguments" only has 0: WebGLShader - ID: 1 & 1: Array Length: 21858 which isn't very helpful because I still can't review the code.

[sebavan]

closing in favor of #283

Spector has never been thought as a tool to help during shader development and it would be great to enhance this area.