Releasing Blosc

Preliminaries

Make sure that RELEASE_NOTES.rst and ANNOUNCE.rst are up to date with the latest news in the release.
Check that VERSION symbols in blosc/blosc.h contains the correct info.

Commit the changes:

$ git commit -a -m"Getting ready for X.Y.Z release"

Create a new build/ directory, change into it and issue:

$ cmake ..
$ cmake --build .
$ ctest

To actually test Blosc the hard way, look at the end of:

where instructions on how to intensively test (and benchmark) Blosc are given.

Create a tag X.Y.Z from master. Use the next message:
```
$ git tag -a vX.Y.Z -m "Tagging version X.Y.Z"
```
Push the previous commits and tag to the github repo:
```
$ git push
$ git push --tags
```

Send an announcement to the blosc, pytables-dev, bcolz and comp.compression lists. Use the ANNOUNCE.rst file as skeleton (possibly as the definitive version).

Edit VERSION symbols in blosc/blosc.h in master to increment the version to the next minor one (i.e. X.Y.Z --> X.Y.(Z+1).dev).
Create new headers for adding new features in RELEASE_NOTES.rst and add this place-holder instead:

#XXX version-specific blurb XXX#

Commit the changes:

$ git commit -a -m"Post X.Y.Z release actions done"
$ git push

That's all folks!