TACHYON-193 TACHYON-194 First drop of Tachyon neo configuration

The PR includes:
-) TACHYON-193
Add new Tachyon properties file configuration to support file based 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.
What about anything that does not come from that file?

At this point in time I don't believe we have any configs that are dynamic
like that but I can see that happening for plugins (if this ever happens
that is...). Plugins would need details and we should not put a lot of them
in that file.

About the comment of reading the keys from the file. How would you interact
with them? I have used configs before that read YAML and created pojos from
them. This was super powerful and simplified many things; have a feeling
that's not what you are getting at though.
On Nov 24, 2014 9:12 AM, "bradley childs" <notifications@github.com> wrote:

> In core/src/main/java/tachyon/Constants.java:
>
> > @@ -49,4 +49,96 @@
> >     * Version 3 [0.6.0] Add lastModificationTimeMs to inode.
> >     */
> >    public static final int JOURNAL_VERSION = 2;
> > +
> > +  // Configurations properties constants.
> > +  // Please check and update Configuration-Settings.md file when you change or add Tachyon
> > +  // configuration properties.
> > +
> > +  public static final String DEFAULT_HADOOP_UFS_PREFIX = "hdfs:,s3:,s3n:,glusterfs:";
>
> Why not just load the names and default values from the tachyon.properties
> file below?
>
> —
> Reply to this email directly or view it on GitHub
> <https://github.com/amplab/tachyon/pull/534/files#r20804852>.
>