sqliteodbc: fix library location

Commit d7d3c8fd828cf6aba4d511be1927458507422a67 (sqliteodbc: update to
0.995, add more metadata) mistakenly moved libraries from $out/lib to
$out (or rather stopped moving them from $out to $out/lib).

Move them back to $out/lib where they're expected to be and referred to
by the /etc/odbcinst.ini snippet.
silver-searcher: updated to 0.19.2

Also fixed the "libgcc_s.so.1 must be installed for pthread_cancel to
work" problem.
proofgeneral: fix build with earlier version of texinfo.