TACHYON-8 [WIP] First drop of Tachyon neo configuration

The PR includes:
-) TACHYON-193
Add new Tachyon properties file configuration.  
Add new code to support Tachyon properties configuration for runtime. 
This will be file based could be overriden via site specific configuration file or override collection in the TachyonConf class.
-) TACHYON-194
Add TachyonConf class to unify all Tachyon configurations.
Use single class TachyonConf to manage the configurations properties as key-value store.

We have a doc for configs at the moment so won't need this here
On Nov 14, 2014 5:29 PM, "Henry Saputra" <notifications@github.com> wrote:

> In core/src/main/resources/tachyon-default.properties:
>
> > @@ -0,0 +1,70 @@
> > +# Default configuration properties for Tachyon
> > +# All of these properties are override-able via tachyon-site.properties file.
> > +
> > +# Common properties
> > +tachyon.home=/mnt/tachyon_default_home
> > +tachyon.web.resources=/core/src/main/webapp
> > +tachyon.underfs.address=${tachyon.home}/underfs
> > +tachyon.underfs.hdfs.impl=org.apache.hadoop.hdfs.DistributedFileSystem
> > +#tachyon.underfs.hadoop.prefixes=
> > +tachyon.underfs.glusterfs.impl=org.apache.hadoop.fs.glusterfs.GlusterFileSystem
> > +#tachyon.underfs.glusterfs.volumes=
>
> The reason I added the empty ones is to allow users to see configuration
> can be set in the file. Maybe we could add doc to refer to Constants
> Javadoc instead.
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/amplab/tachyon/pull/529/files#r20398089>.
>