Consolidate ImageJ entries

[matuskalas]

• https://bio.tools/imagej (mbs_import) - suspicious that the name is ImageJ 2
• https://bio.tools/imagej_nih is more suspicious. Owner is ELIXIR-FR. If this really is a separate code/distro, please document it
• ibid., if the NIH version is a thing and is really provided by IFB ELIXIR-FR, please document why that is so. (@hmenager, who can answer this?)
• ...otherwise investigate whether there are more IFB ELIXIR-FR entries affected with the same problem, and avoid this happening again
  
  

[magnuspalmblad]

https://bio.tools/imagej_nih redirects to https://imagej.net/, which on its landing page shows ImageJ, ImageJ2 and Fiji as the three "main" flavors of ImageJ. https://imagej.net/learn/flavors lists six more non-obsolete flavors. As these have partly different functionality, I would argue they should be separate entries. @zzzZZ-Zhao - is this something you would like to take on, since you are quite familiar with Fiji (and perhaps other flavors)?