Alpha release - October 2016 - Update

winsane: Added extended auth callback with support for context data (#1)
winsane: Zero initialize auth callback variables
winsane: Reset auth callback variables on Exit
coisane: Fixed memory leak in case of unsupported option type
winsane: Fixed memory leak after setting an option's string value
winsane: Fixed memory leak in case of socket reconnect
devsane: Fixed memory leak during creation of device install info
winsane: Fixed socket leak in case of failure during initial connect
wiasane: Fixed invalid memory access if plReceived param is NULL
winsane: Fixed ignored result and logically dead code
winsane: Fixed deleting void pointers with undefined behavior
coisane: Fixed warning about missing break statement
wiasane: Fixed warning about missing break statement
wiasane: Fixed warning about missing break statement
winsane: Added bounds check to tainted length variable
winsane: Added bounds check to tainted record_size variable
winsane: Added bounds check to tainted array_length variable
winsane: Added bounds check to tainted num_options variable
winsane: Added bounds checks to tainted num_values variables
winsane: Fixed bounds checks of tainted variables
installer: Lowered minimal required Windows version to Vista SP1
wiasane: Migrated to extended auth callback with context data (#1)
coisane: Migrated to extended auth callback with context data (#1)
winsane: Enforce range constraint for fixed double values
winsane: Fixed and aligned range constraint to saned server
winsane: Enforce boolean constraint for double values
winsane: Fixed string list constraint to include string length
winsane: Separated value validation into type-specific functions
winsane: Added generic- and type-specific value constrain functions
winsane: Added function to create device directly from name
winsane: Added function to get session device directly from name
winsane: Fixed warning about possible return of invalid memory
winsane: Fixed possible memory overflow after string copy
winsane: Fixed string constrain algorithm to detect full matches
coisane: Added support for unlisted e.g. non-local scanners
wiasane: Added support for unlisted e.g. non-local scanners
wiasane: Fixed possible memory leak by re-using existing device
winsane: Renamed and consolidated device creation methods
Installer: Removed obsolete Windows 95/98/Me version number
Installer: Hardcoded VS2012 / VC110 CRT redistributable DLLs
devsane: Align resource file with other binaries
coisane: Fix possible invalid memory access
wiasane: Improve mode value mapping conditions
wiasane: Fix source value mapping conditions
wiasane: Fix possible memory leak if two valid values exist
wiasane: Add debug output for unsupported commands
signtool: Always use production signmode for debugging on Windows 10
wiasane: Add debug output to session and device handling
wiasane: Add debug output to driver interface
wiasane: Fix scanning of multiple pages using ADF (#2, #16)
Update copyright year of relevant files
Update COPYING and README.md
Update code signing certificate