swift constraints middleware is undocumented

Change-Id: Ie4588e052fd158314ddca6cd8fca9bc793311465 on Sept 5th 2012 introduced new functionality to swift that made previous hard-coded constants into configuration variables.

These need to be added to the documentation

[swift-constraints]

# max_file_size is the largest "normal" object that can be saved in
# the cluster. This is also the limit on the size of each segment of
# a "large" object when using the large object manifest support.
# This value is set in bytes. Setting it to lower than 1MiB will cause
# some tests to fail. It is STRONGLY recommended to leave this value at
# the default (5 * 2**30 + 2).

#max_file_size = 5368709122

# max_meta_name_length is the max number of bytes in the utf8 encoding
# of the name portion of a metadata header.

#max_meta_name_length = 128

# max_meta_value_length is the max number of bytes in the utf8 encoding
# of a metadata value

#max_meta_value_length = 256

# max_meta_count is the max number of metadata keys that can be stored
# on a single account, container, or object

#max_meta_count = 90

# max_meta_overall_size is the max number of bytes in the utf8 encoding
# of the metadata (keys + values)

#max_meta_overall_size = 4096

# max_object_name_length is the max number of bytes in the utf8 encoding
# of an object name

#max_object_name_length = 1024

# container_listing_limit is the default (and max) number of items
# returned for a container listing request

#container_listing_limit = 10000

# account_listing_limit is the default (and max) number of items returned
# for an account listing request
#account_listing_limit = 10000

# max_account_name_length is the max number of bytes in the utf8 encoding
# of an account name

#max_account_name_length = 256

# max_container_name_length is the max number of bytes in the utf8 encoding
# of a container name

#max_container_name_length = 256