Bump version number to v0.7.4

Disable Travis-CI wheel uploading and bump to v0.7.3

Travis-CI default wheels are not suitable for uploading to PyPI (as they can only be installed on a very small number of platforms) and throw an error. Therefore, the uploading of wheels from Travis-CI should be disabled.

Fix references and bump to version v0.7.2

Bump to version v0.7.1

Add build badges to README.md, update wording

Update configure script

Set Version 0.6 and regenerate configure

Set version to 0.4 and regenerate configure script

Recreate configure for 0.4 release

Set version to 0.4