Create a SciJava Searcher for Ops

Would provide graphical access to SciJava Ops. Could derive a new version from the ImageJ Ops [`OpSearcher`](https://github.com/imagej/imagej-ops/blob/ad6a2f4ddba2fe4f2051db74be898e3e32714e1c/src/main/java/net/imagej/ops/search/OpSearcher.java#L64). 

Tangentially related to #246