ruby: pretty-print /std/string as a string
define Typelib::TYPELIB_LIB_DIR

This is mostly for the benefit of syskit, so that typelib files
get listed in Roby's framework paths
ruby: increase verbosity of error message
greatly improve the performance of nameSort

The current implementation was tokenizing the names to do the
comparison. Replace by a much simpler character-by-character
comparison function.

It has a direct impact on everything that adds lots of types,
such as import and merge operations.
call #apply_changes_from_converted_types before calculating the byte array (closes #349)
ruby: remove support for 1.8 and 1.9.1
cmake: check that ruby is version 1.9 or later
ruby: allow to unmarshal byte arrays with non-standard marshalling options
do metadata merge by iterating on the given registry instead of on 'this'

The usual is to merge a small registry into a big one
properly benefit from the merge stack when doing the type comparison
ruby: fix access to nil @exported_templates in #find_exported_templates
ruby: documentation
ruby: define Type.to_xml
fix Type.to_xml
ruby: make from_ruby call apply_changes_from_converted_types on the returned value

It is assumed that the value returned by from_ruby can be used
as a typelib value, i.e. directly on a C++ interface. However,
if apply_changes_from_converted_types does not get called, the
underlying C++ structure is not up-to-date (and therefore the
assumption is broken)
ruby: do not override custom convertions to/from Hash and Array by the default ones
ruby: make sure that we interpret all metadata as UTF-8
ruby: fix source code line for struct/class/enum

GCCXML reports the line of the opening bracket ({) while we really
would like the definition line (struct/class/enum)
ruby: small style fix, remove duplicate call to resolve_type_id
ruby: test for proper parsing of files containing utf-8 characters