Allow translation of messages returned by asdict

Fix #152
Document translate argument of Invalid.asdict
Fix syntax errors in documentation.
Documentation: correct subclassing SchemaNode examples.

Fixes #149 and fixes #155.
cut-n-paste documentation error
need to test if we have a datetime.time first as bool(datetime.time(0)) evaluates to False, but should be considered legitimate
added change to CHANGES.txt
increase TLD length check. fixes #159

Based on list of current valid TLDs
https://data.iana.org/TLD/tlds-alpha-by-domain.txt
add change log entry
Merge pull request #165 from claytron/issue_159_email_validation

increase TLD length check
fix serialization of default with drop

fixes #139
Merge pull request #167 from claytron/issue_139_default_drop

fix serialization of default with drop
Resolve changelog conflct.
Merge branch 'asdict-i18n' of https://github.com/makinacorpus/colander

Conflicts:
	CHANGES.txt
	CONTRIBUTORS.txt
Merge pull request #161 from kotnik/subclschema

Documentation: correct subclassing SchemaNode examples.
Merge pull request #160 from kotnik/synerr

Fix syntax errors in documentation.
Update german translation
Merge pull request #176 from rbu/update-german-20140602

Update german translation
Add myself to CONTRIBUTORS
Update French translations