flesh out README

README.md

 # Time Tracking Analysis
+
+Analyze time tracking data.
+
+## Dependencies
+
+- JDK 8
+- SQLite 3
+- [Ammonite](http://www.lihaoyi.com/Ammonite/#Ammonite-REPL)
+
+## Usage
+
+1.  Create a database for your **debit** work hours:
+
+    ```
+    sqlite3 timetracking.db 'create table debit (day text primary key, hours real)'
+    ```
+
+2.  Fill the database with your **debit** work hours:
+
+    ```
+    sqlite3 timetracking.db 'insert into debit (day, hours) values ("2017-03-28", 8)'
+    ```
+
+3.  Start analysis:
+
+    ```
+    amm ttanalysis.sc timetracking.db export_all.csv
+    ```