Inclusion of RADMeth into MethPipe

Here is a high-level summary of changes I made on `dmr-merge` branch: 
- added RADMeth to MethPipe 
- moved the source code of `dmr` and `methdiff` programs to their new home in `radmeth/` folder
- changed the revant Makefiles

There are a bunch of small and large changes that I plan to do, but I thought that this might be a good time to merge `dmr-merge` branch to `master`. Are there any scripts or anything else that will be affected by the migration of  `dmr` and `methdiff` programs?