Make the solution compilable on a machine with VS14 only
Add support for VS 14

All features seem to work now.
Merge pull request #580 from dungpa/dev14

Add support for VS 14
Check union cases for invalid chars - relates to #567
Create a function which check type names
Check types before rename
Encapsulate displayed full name only when validation succeeded
"Full name:" label in rename dialog
Add another type name test
Merge pull request #576 from forki/Rename

Check union cases for invalid chars - relates to #567
Move them change handling out of the package

Now MEF composition doesn't happen in Package.Initialize anymore.
At least package load has a higher chance to succeed and MEF composition
error no longer makes the whole extension unusable.

Related to #583.
Remove an unused field
Merge pull request #584 from dungpa/fix-package-load

Move theme change handling out of the package
Generic type parameters shouldn't be escaped - fixes #585
Merge pull request #586 from forki/Rename

Generic type parameters shouldn't be escaped - fixes #585
translate SnapshotSpan into current Snapshot in ResolveUnopenedNamespaceTagger
Remove unused declarations and redundant open statements
Do not copy Visual Studio dlls to output folder
Reinforce code style
Merge pull request #589 from vasily-kirichenko/fix-resolve-unopened-ns-bug

translate SnapshotSpan into current Snapshot in ResolveUnopenedNamespace...