Implemented for QFQ session. The T3 FE session still survive.

Introduce new config var 'DB_UPDATE' in config.qfq.ini. Update the handling, if there exist table 'form' and 'Form'.
Manual.rst:  document the new config option DB_UPDATE.
Database.php: Typo fixed.
DatabaseUpdate.php: Iterate over all found 'Form' tables, take the newest version number. Respect config option DB_UPDATE. Fixed a problem: if in the PHP DB updates a newer DB Version is configured than the PHP source itself is, such updates are now not played anymore.
Config.php, QuickFormQuery.php, config.example.ini: handle config setting DB_UPDATE.

#3568 / Form: fuer alle Buttons (save, close, new, delete) eine optionale class & text konfigurierbar machen
Manual.rst: new configuration options listed at config.qfq.ini and Form.paramtert.
Config.php: Defaults configured for F_SAVE|CLOSE|DELETE|NEW_BUTTON_TEXT|TOOLTIP|CLASS|GLYPH_ICON.
BuildFormBootstrap.php: Changed code to take values from config.qfq.ini or (if given) from form.parameter definitions.
QuickFormQuery.php: Copy new setup values from config.qfq.ini to Form.
StoreTest.php: update unit test for new global configuration values
config.qfq.example.ini: fill with new commented key/value pairs.

Manual.rst: added documentation for new config.qfq.ini variables GFX_EXTRA_BUTTON_INFO_INLINE, GFX_EXTRA_BUTTON_INFO_BELOW.

Config.php: new function attackDetectedExitNow().
Sip.php: replace local sleep(PENALTY_TIME_BROKEN_SIP) with central function attackDetectedExitNow().

Manual.rst: notes how to setup length-exceptions to SECURITY_GET_MAX_LENGTH
config.php: implemented special handling of GET vars, named with '..._<num>'.

Add `sqlLog` and `sqlLogMode` to QFQ tt-content records.
Add mode 'error' and `none` to sqlLogMode.
Manual.rst: Added explanations for SQL_LOG, SQL_LOG_MODE, and tt-content pendants sqlLog, sqlLogMode. Update config.qfq.ini to latest attributes.
Database.php: rename $mode to $currentQueryMode to make it more descriptive. Recode dbLog().
Logger.php: do nothing if there is no file defined.
Report.php: new function checkUpdateLog().
Config.php: Set defaults for config.qfq.ini SQL_LOG and SQL_LOG_MODE
Store.php: Fix problem that an empty SQL_LOG will be prependad with SYSTEM_PATH_EXT.

Implement additional 'SHOW_DEBUG_INFO = download' to track down problems with 'session forwarding'.
Configure constants for SHOW_DEBUG_INFO for yes|no|auto

Implemented defaultEscapeType. configurable via config.qfq.ini (global) and per Form.
Implemented max GET parameter lenght. Default: 50. BTW: in phpunit test there have been a parameter 'file' which exceeds the limit of 32.

Config.qfq: Skip empty variable names - happens in phpunit tests. Read new `systemEscapeTypeDefault`.
Constants.php: renamed  TOKEN_LDAP_ESCAPE_* to TOKEN_ESCAPE_LDAP_*. Add TOKEN_ESCAPE_MYSQL, TOKEN_ESCAPE_NONE
Database.php: Set charset to real_escape_string() functions properly. Proxy for mysqli::real_escape_string()
Evaluate.php: Respect global escapeTypeDefault. Implement
formEditor.sql: add column `escapeTypeDefault`. Add FormElement 'escapeTypeDefault'.

Config.php: Defaults are now set in Config.php, not in Store.php anymore. New function setDefaults(), checkForAttack().

Manual.rst: Update Doc for new option 'bsColumns'
Config.php: Copy new element from general config.
Store.php: set default for 'bsColumns'.
QuickFormQuery.php: wrap whole form in 'col-md-XX'

Store.php: reading of config.qfq.ini moved to new class Config.php.