Reserved word warning config

This commit removes reserved word warning from the Browse pages and the
warning on structure page can be switched on/off using the config
variable $cfg['ReservedWordWarning']
Added ability to disable MySQL reserved word warning

Disable MySQL reserved word warning $cfg['ReservedWordDisableWarning'],
documentation and ability to change from prefs pane
Merge pull request #216 from ayushchd/reserved_words_issue

Reserved words issue
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Merge remote-tracking branch 'origin/master'
Update po files
Merge remote-tracking branch 'origin/master'
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Fix "Invalid argument supplied for foreach()" in case a DROP TABLE x statement was typed
Merge branch 'master' of github.com:phpmyadmin/phpmyadmin
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Removed useless code
Fixed bug with refreshing the page in add/drop index
Merge branch 'master' of git://github.com/phpmyadmin/phpmyadmin into contest-4