Currently the default version number in the .control files is set to 1.0
postgres=# CREATE EXTENSION adaptive_counter;
ERROR: could not stat file "/usr/share/postgresql/9.1/extension/adaptive_counter--1.0.sql": No such file or directory
Fix the version number in the .control files
Merged most of the changes from pull request #1 - had to be done
manually, because of the other changes. The only changes skipped
are changes int32 -> int4 (I'm already using int32 in the code,
so I've kept it for consistency - I'm not aware of any difference).
Merged most of the changes, except for the int32 -> int4 changes.
See commit: cc6e77f