csscomp/opensource: Bump dev version after release to maven
csscomp/opensource: Bump dev version after release to maven

This fixes the <project> in the POM.  Previously it references an
undeclared namespace which prevented it from working with the
maven-{help,version}-plugins.
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=132587444

google/closure-stylesheets,google/postcss-rename,google/postcss-rename