{lib}mediainfo{-gui}: 0.7.75 -> 0.7.76

From the changelog:
```
Version 0.7.76, 2015-08-06

+ XML output: line breaks and indents in between attributes for readability
+ Trace feature: XML trace update, only if compiled with trace feature
+ Amazon S3 support (REST API v2), CLI/DLL only and if compiled with
  libcurl support
+ FFV1: improved slice analysis (currently activated only with trace
  feature and for 1st frame)
x MXF: optimization of the parsing, reading a lot less data (e.g. can be
  reduced from 1 GB to 10 MB with some UHD files)
x MXF: wrong frame count with files not having the video stream as the
  first stream
x Dolby E in MPEG-TS: "SMPTE ST 302" information was accidentally removed
x MPEG-TS: avoid filling delay from file name, not applicable on MPEG-TS
x MXF: better handling of huge padding blocks, better handling of
  descriptors without link to a TrackID
x IMX: streams claiming that they are IMX are actually pure MPEG Video,
  probing both IMX and MPEG Video

```