Fix for issue #149
miscellaneous tweaks from aringlis.
included mission and instrument references for all the supported map sources
added in FITS reference
added in SSW reference
lightcurve data source references
spectra data source references
manual merge-in of master.
merging with master
small correction
fixed extra tab character
changed listing 1 to use demo file.
changed caption for listing 1.
cleaning up citation styles
cleaning up citations
fix for listing 6
Merge pull request #156 from wafels/references

References
Merge pull request #154 from aringlis/misc_fixes

Miscellaneous tweaks from aringlis.
Merge pull request #157 from aringlis/listing1

Changed listing 1 to use SunPy demo file
Merge pull request #158 from aringlis/listing6

Fix for code in listing 6