Forward port of '#298996 reported gusgsm1, patch by myself' and '#263790 reported by Micha1111, patch by myself'

#288117 reported by Bartezz, fixed by myself: avoid that people run potx-cli.php from the web, since it was not designed so. tell them to use the module web interface.

#205100 by phirdina: plural translations were missing in exported po files due to bugos database logic

 - updated documentation to match actual behaviour (folding, tab title)
 - some code style changes from the 6.1 version
 - ported region name and default user role detection from 6.1
 - ported duplication marking for installer strings in runtime export from 6.1

#201253 report by Gocho, fix by myself: source strings already had quotes escaped, which is bad for translation lookups

Add error message to case when we found a hook_perm() implementation but there were no recordable permissions provided there. Based on findings in http://drupal.org/node/191964#comment-631556

 - remove hook_node_types() as it is not supported since 4.6
 - silent status reporting now collects messages for later retrieval
 - support for extracting strings from themes, not only modules
 - coder plugin support: provides a code review for coder module

 - do not merge small files into general.pot
 - do not merge occurance of strings in same subproject (subfolder) to general.pot,
   only merge real cross-subproject occurances
 - merge .pot files generated for same subfolder (all will be imported in the same batch
   anyway). although this makes .pot size a bit bigger, it is easier to handle
   by hand, and the file size still looks low

Enable potx to parse Drupal 5 or Drupal 6 source files on request (only implemented in the API for now)

 - we use dots in file names so we should use pathinfo() instead of plain old explode()
 - added JS parsing based on core regex code with custom error reporting, now parsing .js too
 - watchdog() parameters changed, now t() should not be used
 - the menu hook changed, we identify title and description values if literals (otherwise throw an error)
 - format_plural() calls now accept arguments, so we allow a comma after the plural string
 - .info file format changed, so we need to use drupal_parse_info_file() for parsing

Note that I did not implement a code extract for the error message due to some laziness
(it requires watching until the line end, for which we have no code yet, and it needs
to take nesting into account), otherwise new functionality signals errors as before.

(This code also helped identify some watchdog(t()) issues in Drupal 6 which I'll file an issue to fix).

Update (the interface) to Drupal 6 with coder module and also fix coding style issues identified by coder module
Note: the extraction still needs a lot of love to be upgraded to Drupal 6 properly

 - back with the translation exports, but initially just choosing the template language
 - fill in template header with language dependent values if language is choosen
 - option to include translations in the export now with proper plural support

Fix file name generation regex shortcoming identified why checking ubercart issues listed at #177763

#155106 and #155108 patches by myself: blacklist potx.inc, although this makes generating templates for potx itself a manual-only process, but other modules will have their templates generated without the potx.inc cruft. Also fixing the issue when we have no strings collected for a specific area (runtime or installer strings).

#149280 by myself: whitelist 'name', 'description' and 'package' keys from .info files as other values are cropping up, which we don't need for translation, so a blacklist approach was not feasible; thanks for Alexander Hass who reported the issue.