Semigroups no longer compiles with recent git versions of libsemigroups

[wilfwilson]

...because recent git versiona of libsemigroups no longer include a .VERSION file, and the configure script for Semigroups fails when it does not find it. This doesn't affect released versions of Semigroups.

(Using the current stable-1.2 of libsemigroups and stable-3.3 of Semigroups):

configure: using included libsemigroups...
checking for libsemigroups/include/libsemigroups/libsemigroups.hpp... yes
checking for libsemigroups/.VERSION... no
configure: error: libsemigroups version 1.0.6 or higher is required

[james-d-mitchell]

Right, I know how to fix this, an oversight, albeit a terrible one :(

[james-d-mitchell]

This was resolved by PR #693 and since the issue shouldn't impact the release version of Semigroups (since there we use the release version of libsemigroups which does include the .VERSION file), I'll close the issue now.