Merge pull request #4 from rossrowe/master

Added some more unit tests
Move the coverage plugin to buildconfig
add more tests for date field validation and min max validation fro edge case
changed coverage plugin to point at the latest, and checked it worked :-)
Added more tag tests for number and fixed the range setting of the size and maximum minimum values. Need to check validation for max min on numbers.
Added some more information to tutorial
Add number validation and min max attributes form number elements
Add Tests for number Max Min and Range
Refactored out some common code for get number min/max and applied to FormTagLib number tag
Added some more information to tutorial
Merge branch 'master' of https://github.com/nerdErg/GoodForm
Fixed assertion error