Update README.md

update grape-entity URLs
Merge pull request #405 from ngpestelos/patch-1

Update README.md
Update CHANGELOG.md
Fix #407: specifying 'default_format' will also set the default POST/PUT data parser to the given format.
add pry-debugger
present with multiple entities using optional symbol
update README and CHANGELOG for present with multiple entities
ruby 1.8 compatible
make some minor changes as @dblock suggested. : )
Merge pull request #410 from niedhui/present_mutil

Present with multiple entities using optional symbol
fix a trivial mistake in a comment
Merge pull request #411 from jugyo/patch-1

fix a trivial mistake in a comment
Fix #412: specifying  will also override the selection of the data formatter.
Fix #383: Inherit settings correctly when performing nested mounts
Merge pull request #416 from seanmoon/fix-mount-nesting

Fix #383: Inherit settings correctly when performing nested mounts
Update CHANGELOG.md
goliath passes request header keys as symbols
Merge pull request #408 from icflix/goliath-headers

goliath passes request header keys as symbols
Fix #417: Rails 4 does not rewind input, causes POSTed data to be empty.
Better rewind semantics.