<version> in pom.xml

[Daniel Pocock <daniel@pocock.pro>]

Many Maven upstreams have a <version> for each plugin and dependency in
pom.xml

Maven seems to work with precise versions whereas Debian often uses
minimum version or a range constraint for more flexibility.

libphonenumber upstream agreed to remove the version constraint from
pom.xml so it just uses the available plugin versions in
/usr/share/maven-repo

However, now Maven gives a lot of warnings.  Should they put the
constraint back in?  Will maven-debian-helper still be able to build the
package even if Debian doesn't have the exact plugin versions specified
by an upstream in their pom.xml?

upstream commented that the Maven warnings are particularly critical of
people who don't specify precise versions, e.g:

"future Maven versions might no longer support building such malformed
projects."