Updated/added license headers of all files according to new configura…

[RadekKoubsky]

…tion of license-maven-plugin.

See issue #80

I have changed the configuration of license-maven-plugin:

• license is added to all type of files listed in header model http://www.mojohaus.org/license-maven-plugin/header.html
• removed start/end tag "---------/" which causes invalid character "-" in comments in the xml files
• added <failOnMissingHeader>true</failOnMissingHeader>

I removed all license headers and add new license headers according to the new configuration using goal mvn license:update-file-header to make all headers consistent.

Building script contains goal license:check-file-header -Dlicense.licenseName=apache_v2 to check missing headers before build.

[marvec]

The headers were intentional because the plugin did not recognize the headers properly without them.

[marvec]

They were there to fix a problem. So unless you figure out what problem it was and come up with a solution that fixes both issues, we cannot merge this, sorry.