Added a Java Properties format configuration file for OpenTSDB. It's fully backwards compatible in that you can still use the existing command line options, which will overload defaults or config file options, but it can let you save a config file in a certain location and use any of the TSD CLI tools without passing extra parameters.
Sample config file is at src/opentsdb.conf
The Config class has helpers to convert values to numbers or boolean
Modified all of the code that used to reply on System properties or other means to use the new Config class
Docs will be up on the website shortly