Better support for using field names and rule parameters in error messages.
Merge branch 'refs/heads/develop' into feature/form_error_msgs
Merge branch 'develop' of https://github.com/EllisLab/CodeIgniter into feature/form_error_msgs
Merge branch 'develop' of https://github.com/EllisLab/CodeIgniter into feature/form_error_msgs

Conflicts:
	system/language/english/form_validation_lang.php
Fix a merge oopsie in the language file.
Combine this feature with Fix Issue #935 in another pull request.
Added CI_Output::get_header()

(an improved version of PR #645)

Also fixed get_content_type() to only return the MIME value and created
Output library unit tests for both of these methods.
Fix #2041
Add CI_Output::delete_cache()

(an improved version of PR #609)
keep_flashdata array test
Merge pull request #2043 from johnathancroom/keep_flash_data_array

Test for keep_flashdata accepting an array
config->site_url() optimizations

- direct access to config array, instead of item() calls
- the string cast is just in case 'url_suffix' would be set to false or null; the function produces the same results without this cast, but it leads to a robuster code, as false and null are sanitized and skip the suffix insertion code
- altered conditional structure: if no suffix, skip the appending of an empty string to $uri
config->site_url(): remove useless cast

thanks to narfbg
Merge pull request #2048 from vlakoff/develop

config->site_url() optimizations
[ci skip] Cleaned some spaces
Improve schema support for Postgre
Add min_width and min_height options to the Upload class

(manually implementing outdated PR #636)
Fix postgre db_connect()
Added small improvement to the _remove_evil_attributes function

Signed-off-by: brian978 <dbrian89@yahoo.com>
Rename DB_result _data_seek() to data_seek() and make it publicly available

(as requested in #2050)