Refixed: 1131 error trying to load saved survey under mssql
Refixed: 1133 exported files contain only the SELECT statement
Fixed: 1132 statistics data type error (mssql)

I changed the db_quote_id function (inf common.php to quote properly in the case of MSSQL we should use this function each time we have to refer a field in the database.
The variables $FieldMarkerLeft and $FieldMarkerRight were removed.

git-svn-id: file:///Users/Shitiz/Downloads/lssvn/source/limesurvey@3155 b72ed6b6-b9f8-46b5-92b4-906544132732