Fix SourceNode.fromStringWithSourceMap for empty maps.

Without this fix, if aSourceMapConsumer.eachMapping executes its callback zero
times, the lastMapping passed to the "remaining code" call to addMappingWithCode
will be null, causing a crash.
Merge pull request #70 from meteor/empty-source-map

Fix SourceNode.fromStringWithSourceMap for empty maps.
Bumping version number to 0.1.26
Make file parameter optional for SourceMapConsumer

UglifyJS doesn't write the parameter, the specification doesn't state
whether it is required, and it's not actually used anywhere in
source-map.
Merge pull request #71 from txase/master

Make file parameter optional for SourceMapConsumer
Bumping version to 0.1.27
Preserve name indices for duplicate names

Without this fix, ArraySet objects only added the first copy of a name
if the "names" array contained duplicates. This messed up indices into
the names array because the array was shorter than it should be. The
TypeScript compiler sometimes generates source maps with duplicate
names, causing a crash in SourceMapConsumer.
Deduplicate names for generation, also added tests
Hard-code test source maps to avoid breaking encapsulation
Merge duplicate mappings while generating a source map from SourceNode

This results in smaller maps.
Merge pull request #75 from sokra/source-node-merging

Merge duplicate mappings while generating a source map from SourceNode
Bumping version to 0.1.28
Merge branch 'master' of git://github.com/evanw/source-map into github-issue-72
Fixing up small style nits and linking relevant github issue and bugzilla bug in comment.
Merge branch 'github-issue-72'
Bump version number to 0.1.29
Adding examples to the README
Merge branch 'examples'
Don't join data URIs
Merge pull request #77 from fitzgen/dont-join-data-uris

Don't join data URIs