A little utility to manage a simple time-sheet file.
 
 The file-format is this:
 
 ```
 -- Someday YYYY-MM-DD

    start@HH:MM[:SS][(+|-)NN(mins|hrs)][,HH:MM[:SS][(+|-)NN(mins|hrs)]]

    Client Name: This is a memo.	
 ```
 

 The parser currently has some rudimentary error handling: it detects invalid indentation (i.e. the lines of
 a record do not begin with either a single tab or three spaces) and it detects invalid times.
 
 Additionally, if run in interactive mode `-i`, when it discovers invalid input, it will prompt for a replacement
 and attempt to correct the error.  Also, with `-W`, it should be able to recover from whitespace errors on its own.
 
 ## Todo:
 
 - Expand error handling
 - Add alternative export formats
 - Add querying capabilities
 - Support some notion of sub-tasks
 
 ## Examples:

 
 ```
 % ./timesheet -h

 timesheet file parser, version 0:4
 -c --client                     boolean  Sort by client
 -r --reverse                    boolean  Reverse sort
 -W --ignore-whitespace          boolean  Ignore whitespace errors in input
 -i --interactive                boolean  Run Interactively
 -v --version                    boolean  Version
 -s --status                     boolean  Print a summary of the hours worked and the prices
 -h --help                       boolean  show help
 ``

 By default, it orders the log by dates.  With the `-r` option, it displays the dates in descending order:
 

 ```
 % ./timesheet -r sample-inputs/test.ts
 Thu, 2016/01/04  Client #2    5.00 hrs  Implement prototype and write presentation
 Thu, 2016/01/04  Client #1    9.00 hrs  Implement Facebook Connector
 Wed, 2016/01/03  Client #2    2.50 hrs  Discussed user requirements and produce specification.
 Wed, 2016/01/03  Client #1    6.00 hrs  Delivered prototype, reviewed prototype feedback.
 Tue, 2016/01/02  Client #1    8.00 hrs  Prototype for testing user experience.
 Mon, 2016/01/01  Client #1    8.00 hrs  Mockup of site layout
 ```
 

 With `-c` it sorts by clients and then does a stable-sort by date:
 

 ```
 % ./timesheet -sc sample-inputs/test.ts
 Mon, 2016/01/01  Client #1    8.00 hrs  Mockup of site layout
 Tue, 2016/01/02  Client #1    8.00 hrs  Prototype for testing user experience.
 Wed, 2016/01/03  Client #1    6.00 hrs  Delivered prototype, reviewed prototype feedback.
 Thu, 2016/01/04  Client #1    9.00 hrs  Implement Facebook Connector
 Wed, 2016/01/03  Client #2    2.50 hrs  Discussed user requirements and produce specification.
 Thu, 2016/01/04  Client #2    5.00 hrs  Implement prototype and write presentation
 ------------------------------------------------------------------------------------------------------------------------

                  Client #1:  31.00 hours @   XX.00 $/hr = $XXXX.00
                  Client #2:   7.50 hours @   XX.00 $/hr = $ XXX.00
                      Total:  38.50 hours @   XX.00 $/hr = $XXXX.00

 ```
 
 ```
 % ./timesheet -sr sample-inputs/test.ts
 Thu, 2016/01/04  Client #2    5.00 hrs  Implement prototype and write presentation
 Thu, 2016/01/04  Client #1    9.00 hrs  Implement Facebook Connector
 Wed, 2016/01/03  Client #2    2.50 hrs  Discussed user requirements and produce specification.
 Wed, 2016/01/03  Client #1    6.00 hrs  Delivered prototype, reviewed prototype feedback.
 Tue, 2016/01/02  Client #1    8.00 hrs  Prototype for testing user experience.
 Mon, 2016/01/01  Client #1    8.00 hrs  Mockup of site layout
 ------------------------------------------------------------------------------------------------------------------------

                  Client #1:  31.00 hours @   XX.00 $/hr = $XXXX.00
                  Client #2:   7.50 hours @   XX.00 $/hr = $ XXX.00
                      Total:  38.50 hours @   XX.00 $/hr = $XXXX.00

 ```
 

 `-c` and `-r` combine:
 

 ```
 % ./timesheet -scr sample-inputs/test.ts
 Thu, 2016/01/04  Client #2    5.00 hrs  Implement prototype and write presentation
 Wed, 2016/01/03  Client #2    2.50 hrs  Discussed user requirements and produce specification.
 Thu, 2016/01/04  Client #1    9.00 hrs  Implement Facebook Connector
 Wed, 2016/01/03  Client #1    6.00 hrs  Delivered prototype, reviewed prototype feedback.
 Tue, 2016/01/02  Client #1    8.00 hrs  Prototype for testing user experience.
 Mon, 2016/01/01  Client #1    8.00 hrs  Mockup of site layout
 ------------------------------------------------------------------------------------------------------------------------

                  Client #1:  31.00 hours @   XX.00 $/hr = $XXXX.00
                  Client #2:   7.50 hours @   XX.00 $/hr = $ XXX.00
                      Total:  38.50 hours @   XX.00 $/hr = $XXXX.00

 ```