First steps
Reader ready
- Reader added as the main function for reading a file of urm format

* It only supports '*.urm' files and POSIX format
URM class ready
- The URM class now can retrive an object that contains the formal mode of the URM.

* It includes:
  * conditions: the initial conditions stablished on the file as the first line
  * instructions: the set of instructions in uppercase
  * elements for formal configuration: P,M,PC
Basic URM Model.

- In this point, the for operations are necessary to continue