Supporting cursor direction

ORDER BY was always ascending, ignoring the IDBCursor direction.
suggested solution in #73 implemented as pull request
fix errors in some browsers
Merge pull request #130 from k2s/hokan

suggested solution in #73 implemented as pull request
Fixed code style
Fix build warning
correct capitalization of indexedDB on Readme

before it said window.IndexedDB, now it's window.indexedDB.
Merge pull request #131 from marianoguerra/patch-1

correct capitalization of indexedDB on Readme
Dual license under MIT and apache
Handle non-IDBKeyRange range objects (http://www.w3.org/TR/IndexedDB/#widl-IDBObjectStore-openCursor-IDBRequest-any-range-IDBCursorDirection-direction).
Handle non-IDBKeyRange range objects (http://www.w3.org/TR/IndexedDB/#widl-IDBObjectStore-openCursor-IDBRequest-any-range-IDBCursorDirection-direction).
Update IDBObjectStore.js

Check if primary key is undefined, instead of just (!primaryKey), as if a primary key is 0 we would still want to continue with the callback and not get the next auto-increment key.
Reset prefetched data after update or delete.
New build with latest changes
Fix typo in comment
Fix callback scheduling when we are checking existence of dbVersions table

I made a test case:

db = window.openDatabase("foo", 1, "Foo", 4*1024*1024)

_.times(2, function(n) {
  db.transaction(function(tx) {
    console.log("transaction"+n);
    tx.executeSql("SELECT * FROM dbVersions", [], function(t, data) {
      console.log("transaction success"+n);
    });
  }, function() {
    console.log("error"+n);
    db.transaction(function(tx) {
      console.log("error transaction"+n);
    });
  }, function() { console.log("success"+n)});
})

The error transaction ends up getting scheduled after transaction 2.  If a user had called .open() before the error transaction
had run then the open() transaction would try to access the uncreated dbVersions table.
Check in buil changed dist files
Upgrade node version

TravisCI is failing to run npm install.  I suspect its because its
running an old version of npm.  Upgrading node should fix that
Merge branch 'incoming-pr' of https://github.com/mattjacobsen/IndexedDBShim

Conflicts:
	dist/IndexedDBShim.min.js
	dist/IndexedDBShim.min.map
Merge branch 'mattjacobsen-incoming-pr'