Fix for IZPACK-861 No Dutch language
Renamed the following langpack resources and their corresponding flags:
* cze -> ces. Replace Czech Republic country code with language code
* ned -> nld. Replace country code with language code
* por -> bra. Language pack contains Brazilian Portuguese messages. Replace  Portuguese language code with Brazilan
country  code.
* svk -> slk. Replace Slovakia country code with Slovakia language code
* rom -> ron. Replaced outdated Romanian country code (now ROU) with language code
* mys -> msa. Replaced Malaysia country code with language code
* scg -> srp. Language pack contains Serbian messages. Replaced Singapore  country code with Serbian language code.
*ind -> idn . Language pack contains Indonensian messages, but the language code (idn) is indistinguishable from the
lower case India country code (IND). Renamed to Indonesian country code to avoid potential conflict
Fix messages retrieval by country code.
Display Portuguese rather than Brazilian Portuguese
[IZPACK-862] Installation in one existing folder not working
Code cleanup in TargetPanel
Merge pull request #69 from rkrell/master

[IZPACK-862] Installation in one existing folder not working
Merge pull request #68 from unb/IZPACK-861

Fix for IZPACK-861 No Dutch language
[IZPACK-863] Not possible to set a dynamic plain variable to ""
Merge pull request #70 from rkrell/master

[IZPACK-863] Not possible to set a dynamic plain variable to ""
[IZPACK-864] - Dynamic variables in ConfigurationInstallerListener don't work at all
Merge pull request #71 from rkrell/master

[IZPACK-864] - Dynamic variables in ConfigurationInstallerListener don't work at all
Fix skip panel behaviour
Merge branch 'master' of https://github.com/izpack/izpack
Merge pull request #72 from unb/master

Fix skip panel behaviour
Initial work to separate configuration parsing from UserInputPanel so it can be reused in UserInputPanelConsoleHelper
Refactored UserInputPanel to use GUIFieldView class hierarchy to display fields.
UserInputPanel refactoring
* Moved non-GUI field behaviour into the Field classes.
* Renamed PasswordEncryptionValidator to PasswordEncryptionProcessor. Now implements Processor instead of
Validator interface
UserInputPanel refactoring:
* started implementing UserInputPanelConsoleHelper in terms of Field and FieldView
Adding a new variable to get the selected locale
UserInputPanel refactoring:
* package rename
* expanded test cases