gplugin/gplugin

Make sure all of the license file headers are pointing to an https link

Testing Done:
Compile and docs.

Reviewed at https://reviews.imfreedom.org/r/127/
if get_option('vapi')
shared_library('genie-basic-plugin', 'basic.gs',
name_prefix : '',
dependencies : [gplugin_dep, gplugin_vapi])
shared_library('genie-dependent-plugin', 'dependent.gs',
name_prefix : '',
dependencies : [gplugin_dep, gplugin_vapi])
shared_library('load-exception-plugin', 'load-exception.gs',
name_prefix : '',
dependencies : [gplugin_dep, gplugin_vapi])
shared_library('load-failed-plugin', 'load-failed.gs',
name_prefix : '',
dependencies : [gplugin_dep, gplugin_vapi])
shared_library('unload-failed-plugin', 'unload-failed.gs',
name_prefix : '',
dependencies : [gplugin_dep, gplugin_vapi])
endif # vapi