Make a note that ThreadScope support is currently broken.

README.ThreadScope:
    As above.
Branches: 13.05, master

Workaround the failure of the feedback tests on Windows.

deep_profiler/mdprof_create_feedback.m:
	The feedback tool does not need to set the server or script names in
	the deep profiling data structure.  (They are only required by the
	CGI interface.)  Attempting to determine the server name is currently
	failing on Windows, so just pass a dummy one in the feedback tool
	for now.

	Eventually we should fix this so that (1) CGI interface specific things
	are not part of the deep/0 structure and (2) looking up the hostname
	on Windows works.
Add an extra note about costs in version_array.m

version_array.m did not document the cost of modifying an old part of the
array.  This change adds a simple description.

library/version_array.m:
    As above.
Fix a spelling mistake.

library/version_hash_table.m:
    As above.
Add two new functions to version_hash_table and hash_table

library/version_hash_table.m:
    Provide a new from_assoc_list function that gives the caller more
    control over the new hash table.

    Provide a new function named copy to make a copy of a hash table,
    this makes it easier for programmers to reason about performance when
    using version hash tables.

library/hash_table.m:
    Add the same functions to hash_table.m so both modules have the same
    interface.

NEWS:
    Announce the change.
Merge fixes from 13.05 branch.