removed repositories element

No longer necessary to access the Protege GitHub Maven repository for
the HermiT dependency.  HermiT is available in Maven Central now.
updated scm info

Source code was moved from the old Protege Subversion repository to
GitHub.
updated hermit dependency

Changed this dependency to point to the one that was recently put on
Maven Central, instead of the one in the Protege GitHub Maven
repository.
fixed osgi wiring errors

Upgraded to much newer version of the maven-bundle-plugin.  Modified the
import package directive to fix some osgi wiring errors.
compile against 1.7

Updated compiler plug-in to use 1.7 for source and target.
renamed to .md extension
removed outdated files

Switched to building this project with Maven.  Removed files that were
only necessary for the old Ant build process.
removed outdated file

This file was used in the Ant build process, which has been abandoned in
favor of Maven.