WL#6791 : Redefine client --ssl option to imply enforced encryption

# Changed the meaning of the --ssl=1 option of all client binaries
to mean force ssl, not try ssl and fail over to eunecrypted
# Added a new MYSQL_OPT_SSL_ENFORCE mysql_options()
option to specify that an ssl connection is required.
# Added a new macro SSL_SET_OPTIONS() to the client
SSL handling headers that sets all the relevant SSL options at 
once.
# Revamped all of the current native clients to use the new macro
# Removed some Windows line endings.
# Added proper handling of the new option into the ssl helper
headers.
# If SSL is mandatory assume that the media is secure enough 
for the sha256 plugin to do unencrypted password exchange even
before establishing a connection.
# Set the default ssl cipher to DHE-RSA-AES256-SHA if none is 
specified.
# updated test cases that require a non-default cipher to spawn 
a mysql command line tool binary since mysqltest has no support
for specifying ciphers.
# updated the replication slave connection code to always enforce
SSL if any of the SSL config options is present.
# test cases added and updated.
# added a mysql_get_option() API to return mysql_options() 
values. Used the new API inside the sha256 plugin.
# Fixed compilation warnings because of unused variables.
# Fixed test failures (mysql_ssl and bug13115401)
# Fixed whitespace issues.
# Fully implemented the mysql_get_option() function.
# Added a test case for mysql_get_option()
# fixed some trailing whitespace issues
# fixed some uint/int warnings in mysql_client_test.c
# removed shared memory option from non-windows get_options
 tests
# moved MYSQL_OPT_LOCAL_INFILE to the uint options