Added MimeKit.Cryptography.MD5 for .NETPortable versions of MimeKit
Allow adding binary data as attachment
Add angle brackets to each message-id when serializing the References header

Fixes issue #45
Merge pull request #46 from cmayer0087/master

Allow adding binary data as attachment
Fixed code formatting, added another AttachmentCollection.Add method, and added docs for previous commit
Bumped version to 0.31.0.0
Updated MimeKitLite.nuspec
Merged MimeKitLite.Mobile.sln into MimeKitLite.sln and updated MimeKitLite.nuspec

The next release of MimeKitLite will include the Android and iOS assemblies.
Fixed a bug in MimeParser.StepHeaders()

If we don't advance any bytes this loop, don't set midline to true.

Fixes a case where the '\r' of a blank line that terminates the headers
is the last byte of the previous read(). If we set midline to true, then
what happens is that we assume that the blank line was part of the headers
and never stop scanning the headers until we reach the end of the file.

Thanks to Hugo Hallqvist for finding & reporting this bug.
minor formatting fix
Made X509-related types public

This is a necessary step to make possible to implement different
IX509CertificateDatabase providers and remove the dependency on
Mono.Data.Sqlite.
Removed dependency on Mono.Data.Sqlite

SqliteCertificateDatabase now loads Mono.Data.Sqlite using reflection and
doesn't depend on it explicitly. A new property "IsAvailable" can be used
to determine if SQLite support is available at runtime.

DefaultSecureMimeContext now checks for SQLite support at runtime and
throws an exception if not available. This can be replaced by a better
behaviour in the future (using a different IX509CertificateDatabase) or
left as is.
Merge pull request #48 from fogzot/master

Removal of Mono.Data.Sqlite dependency
Modified DbExtensions.CreateParameterWithValue() to be DbExtensions.AddParameterWithValue()
Don't use reflection for Mono.Data.Sqlite for Xamarin mobile platforms
Added a new .ctor to DefaultSecureMimeContext and made SqliteCertificateDatabase public
Documented most of the newly exposed X509 certificate database APIs
Finished documenting all of the new database APIs
Added a work-around for mail clients that mistakenly quote rfc2184 encoded parameter values

Fixes issue #49
Added more runtime checks to make sure Mono.Data.Sqlite will work