Fixed Content insert fails on 3.2 Postgresql 9.0  

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=32822&start=0
Update postgresql.php

small fix when installing components
PostgreSQL - Later insertions fail after sample data was installed

#### Steps to reproduce the issue

Install sample data.

After this inserting a new article will fail. because it will try to insert it with id=1 (sequence was not incremented). PostgreSQL works a bit different from MySQL.

#### Expected result

No issues inserting new data after sample was installed.

#### Actual result

Fatal SQL errors because of duplicate keys.

#### System information (as much as possible)

PostgreSQL 9.3

#### Additional comments
PK fix for sample_data.sql
Fixed sample_learn.sql
Fixed errors while inserting data.

Some queries fail in PG 9.3 because they are not properly escaped.
Update file.php

Prevents security issue where $file can be an empty string or directory path. If that happens the deletion fails but the directory is left writeable with 0777 permissions. If $file is empty then this is interpreted by chmod as the current director, so root folder of Joomla site is left writeable.
Update file.php
Update file.php
Fix Yes/No Option for the proxy radio

Tracker:
http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=33652
Merge pull request #3448 from fcoulter/staging

Update file.php
Merge pull request #3279 from vdespa/patch-4

[#32822] Fixed Content insert fails on 3.2 Postgresql 9.0
Merge pull request #3294 from vdespa/patch-7

PostgreSQL - Later insertions fail after sample data was installed
Merge pull request #3497 from zero-24/patch-17

[#33652] Fix Yes/No Option for the proxy radio
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