Release: Prepare v2.2.1

Signed-off-by: Stefan Raspl <[email protected]>

CONTRIBUTING.md

@@ -0,0 +1,62 @@
+Contributing to qclib
+=====================
+
+
+License
+-------
+All contributions have to be submitted under the BSD 3-clause license. See also
+the [LICENSE](LICENSE) file.
+
+
+Developer's Certificate of Origin and Signed-off-by
+---------------------------------------------------
+The sign-off is a simple line at the end of the explanation for the patch,
+which certifies that you wrote it or otherwise have the right to pass it on as
+an open-source patch.
+
+With the Signed-off-by line you certify the below:
+
+```
+Developer's Certificate of Origin 1.1
+
+       By making a contribution to this project, I certify that:
+
+       (a) The contribution was created in whole or in part by me and I
+           have the right to submit it under the open source license
+           indicated in the file; or
+
+       (b) The contribution is based upon previous work that, to the best
+           of my knowledge, is covered under an appropriate open source
+           license and I have the right under that license to submit that
+           work with modifications, whether created in whole or in part
+           by me, under the same open source license (unless I am
+           permitted to submit under a different license), as indicated
+           in the file; or
+
+       (c) The contribution was provided directly to me by some other
+           person who certified (a), (b) or (c) and I have not modified
+           it.
+
+       (d) I understand and agree that this project and the contribution
+           are public and that a record of the contribution (including all
+           personal information I submit with it, including my sign-off) is
+           maintained indefinitely and may be redistributed consistent with
+           this project or the open source license(s) involved.
+```
+
+If you can certify the above, just add a line stating the following at the
+bottom of each of your commit messages:
+
+```
+Signed-off-by: Random Developer <[email protected]>
+```
+
+Please use your real name and a valid e-mail address (no pseudonyms or anonymous
+contributions).
+
+
+Submitting code
+---------------
+The preferred way is to create GitHub pull requests for your code contributions.
+Please create separate pull requests for each logical enhancement, new feature,
+or fix.

Makefile

@@ -4,7 +4,7 @@
 #     major : Backwards compatible changes to the API
 #     minor : Additions leaving the API unmodified
 #     bugfix: Bugfixes only
-VERSION    = 2.2.99
+VERSION    = 2.2.1
 VERM       = $(shell echo $(VERSION) | cut -d '.' -f 1)
 CFLAGS    ?= -g -Wall -O2
 LDFLAGS   ?=