implemented a simple boolean matcher.

[cmungall]

This can be thought of as a simple boolean limit case

of other matchers; e.g. jaccard with a floor function.

although this is not anticipated to be useful for the general phenotype search use case, it can be useful to leverage owlsim services for doing basic queries of the form: find all genes with phenotypes A and B but not C

[drseb]

Indeed important!

[cmungall]

Travis seems to be failing due to too much log output, need to investigate...