Added two missing utils function to main doc page
Proper RST formatting from the set_flags_in_fixed_headers method.
Changed the readMSEED() doc to reflect the current state.

timing_quality is now stored under blkt1001. Also added some more
examples and rewrote parts of the docstring. Furthermore non-existing
values when using details=True now will be set to None instead of -1.
Just more pythonic and should not influence any use cases.
Updating writeMSEED() doc.
Changelog.
Merge pull request #1 from krischer/issue855

Documentation related changes.