Some cleanup related to mt_rand()

- min and max values are 0 and mt_getrandmax() by default
- remove useless mt_srand() seed calls
Update user_agents.php

Added the PS Vita User Agent to the list.
Added description to composer.json

When executing "composer validate", an error is generated because there
is no description. Also removed a couple of tabs and replaced them with
spaces to neaten it up slightly.
Modified do_upload() to use UPLOAD_ERR constants.

Modified switchcase in the do_upload() use the UPLOAD_ERR_* constants,
instead of just using an integer, and then commenting out the constant
beside it.
Made set_error() method DRY.
Reverted indenting spaces back to tabs.

(My fault - Sorry!)
Changed spaces to tabs for consistency.
fix typo : StdClass should be stdClass

Signed-off-by: Abdul Malik Ikhsan <samsonasik@gmail.com>
Merge pull request #2367 from vlakoff/develop

User guide: fix list of allowed URI characters
Merge pull request #2371 from thefuzzy0ne/fix/upload_err_constants

Modified do_upload() to use UPLOAD_ERR constants.
Merge pull request #2369 from vlakoff/develop-2

Some cleanup related to mt_rand()
Merge pull request #2375 from samsonasik/fix/typo

fix typo : StdClass should be stdClass
Merge pull request #2303 from lracicot/develop

Add unicode support in cart product name.
[ci skip] Add changelog entries for PR #2303
Removed newline at EOF
Merge pull request #2372 from thefuzzy0ne/fix/composer.json

Added description to composer.json
fixed for styleguide.

|| to OR
remove the empty line at EOF
Fixed for styleguide.
Add common robot user agents.
Merge pull request #2382 from garthkerr/add-bot-agents

Add common robot user agents.