Modernize the autotools build system.
Modernize the autotools build system.

josh-wambua/libdivecomputer,venkateshshukla/libdivecomputer,henrik242/libdivecomputer,josh-wambua/libdivecomputer,glance-/libdivecomputer,glance-/libdivecomputer,Poltsi/libdivecomputer-vms,henrik242/libdivecomputer,andysan/libdivecomputer,venkateshshukla/libdivecomputer,andysan/libdivecomputer