Piwik is a free/libre analytics platform. Refs #4455 GNU Package requirement to use free/libre instead of open source

fixes #4609

(some tests failing)

Added namespaces to functions.php files in the five plugins that had one
Work in progress

Removed many Piwik_ functions, in Piwik 2 it is best practise to use the methods calls instead

Todo: finish converting core/ classes + convert plugins/ classes to use \Piwik\Plugin namespace + fix build + Merge master

Refs #4059 Work in progress: Conversion to use Namespaces: Period*, Metrics, Segment, SegmentExpression, PluginsManager.
Removed some deprecated code.

such as removing duplicate code and a lot of refactoring, the code is now much more readable!

Converting Piwik core source files, PHP, JS, TPL, CSS

More info: http://piwik.org/participate/coding-standards/

git-svn-id: http://dev.piwik.org/svn/trunk@7627 59fd770c-687e-43c8-a1e3-f5a4ff64c105

 * Adding one sentence to one paragraph description of each API (feedback on the actual test is most welcome!)
 * This will be displayed on the API Reference page: http://piwik.org/docs/analytics-api/reference/ 
that's why it's pretty important :)
 * Adding table of contents in the API Page

git-svn-id: http://dev.piwik.org/svn/trunk@4448 59fd770c-687e-43c8-a1e3-f5a4ff64c105

git-svn-id: http://dev.piwik.org/svn/trunk@3270 59fd770c-687e-43c8-a1e3-f5a4ff64c105

git-svn-id: http://dev.piwik.org/svn/trunk@2968 59fd770c-687e-43c8-a1e3-f5a4ff64c105

git-svn-id: http://dev.piwik.org/svn/trunk@2011 59fd770c-687e-43c8-a1e3-f5a4ff64c105

git-svn-id: http://dev.piwik.org/svn/trunk@1832 59fd770c-687e-43c8-a1e3-f5a4ff64c105

git-svn-id: http://dev.piwik.org/svn/trunk@1817 59fd770c-687e-43c8-a1e3-f5a4ff64c105

 * add @category (Piwik => 'core', Piwik_Plugins => 'plugins')
 * in core, use @package and @subpackage more consistently to group files/classes; exception is DataFiles/*, PluginsFunctions/*, and SmartyPlugins/*
 * in plugins, @package is the plugin name
 * removed '@param none' -- not a phpdoc convention
 * '@throws' and '@return void' are also not phpdoc conventions, but are widely used elsewhere, e.g., Smarty & Zend


git-svn-id: http://dev.piwik.org/svn/trunk@1420 59fd770c-687e-43c8-a1e3-f5a4ff64c105

- ADDED search field below data tables is now using the regular expression syntax. For example, a search for "google|yahoo" would match all rows containing "google" or "yahoo". All search strings containing any of the special characters from this list: . \ + * ? [ ^ ] $ ( ) { } = ! < > | must be escaped with a back slash, eg. if you want to search for keywords containing "piwik!" you would search for "piwik\!". 
- ADDED new configuration option: default number of rows returned in API responses "API_datatable_default_limit = 50"
- REMOVED the automatic generic filters. The limit and sort and safe decode are applied by each module when necessary.
- removed exact match filter. Now all searches are using regular expressions syntax. Exact match can be done using ^exact search here$
- fixed notice when natural sort on a non existing column
- fixed CSV export for datatable_array
- clarified code for plotting multiple lines in an evolution chart
- FIXED #624 Added icon "save as image" below all graphs (next to the Export icon)
- moved all JS functions into the piwikHelper static class
- added example in ExampleUI plugin to plot only visits from google and yahoo! in 4 lines of code
- added message when flash is disabled and graph not showing, linking to piwik faq. 
- added expressInstall.swf feature

git-svn-id: http://dev.piwik.org/svn/trunk@1085 59fd770c-687e-43c8-a1e3-f5a4ff64c105

- Introducing the new "ExampleUI" plugin which shows how to plot data easily in Piwik, reusing the existing framework (evolution graph, pie chart, bar graph, sparklines, tag clouds, tables, and more!)

git-svn-id: http://dev.piwik.org/svn/trunk@1084 59fd770c-687e-43c8-a1e3-f5a4ff64c105