- Fixed behaviour of buildnumber-maven-plugin
  to get the revision from version control only once
  in particular in a multi-module build.
Merge pull request #52 from khmarbaise/REVISION-ONLY-ONCE

- Fixed behaviour of buildnumber-maven-plugin
Update URLs to https otherwise github will cache old results of the build badge for security reasons.
Fixes #53 mvn versions:update-properties versions:use-latest-releases (joda-beans, maven-scm-publish-plugin, guava, maven-scm-plugin, joda-convert, slf4j, plexus-utils, logback, maven-artifact, maven-core, maven-plugin-api, httpcomponents)

Updated ${org.joda.joda-beans.version} from 0.9.0 to 0.9.6
Updated ${maven-scm-publish-plugin.version} from 1.0-beta-2 to 1.0
Updated ${guava.version} from 15.0 to 16.0.1
Updated ${maven-scm-plugin.version} from 1.8.1 to 1.9
Updated ${org.joda.joda-convert.version} from 1.5 to 1.6
Updated ${org.slf4j.version} from 1.7.5 to 1.7.6
Updated org.codehaus.plexus:plexus-utils:jar:3.0.16 to version 3.0.17
Updated ch.qos.logback:logback-classic:jar:1.0.13 to version 1.1.1
Updated ch.qos.logback:logback-core:jar:1.0.13 to version 1.1.1
Updated org.apache.maven:maven-artifact:jar:3.1.1 to version 3.2.1
Updated org.apache.maven:maven-core:jar:3.1.1 to version 3.2.1
Updated org.apache.maven:maven-plugin-api:jar:3.1.1 to version 3.2.1
Updated org.apache.httpcomponents:httpclient:jar:4.3.1 to version 4.3.2
Updated org.apache.httpcomponents:httpclient-cache:jar:4.3.1 to version 4.3.2
Updated org.apache.httpcomponents:httpcore:jar:4.3 to version 4.3.2