Fixed #31: moved bodyparsing to allow upload of non-json

[grtjn]

#31

[grtjn]

Needs thorough testing. Saw some weird issues with ml-highcharts. See also #177 (comment)..

[grtjn]

I think I need to take a look at this commit from @ryanjdew, he moved the bodyparser inside router. Interesting.. https://github.com/ryanjdew/slush-marklogic-node/commit/962554609ad168bf12b435c355955cea9be31373

[grtjn]

This looks better, but still needs more testing..

[grtjn]

Missed out on a few important changes to proxy.js, added those. Even a simple search call from UI to backend failed, with these extra changes all seemed fine..

[grtjn]

Works fine with JSON updates, so at least no regression. Would be nice to test this with binary upload too, though..

[grtjn]

Noticed another glitch with the out of the box app-user. It gets a 403, which wasn't handled properly in /user/login. Fixed that.

[grtjn]

Proper app-user privs for accessing UI can be found in #298. Comes down to rest-reader/rest-writer priv..

[grtjn]

Tested this sufficiently, going to merge this PR, as it contains some important fixes..