Do not segfault if camera initialization fails in constructor.
I am merging this pull request. Note that I have merged a previous pull request for EMGain support #6 into master. The RELEASE.md file for R2-5 is now:
R2-5 (July XXX, 2016)
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* Added support for Electron Multiplying (EM) Gain. Thanks to Mike Dunning for this.
* Add ability to set the BaselineClamp in the Andor SDK. Thanks to Matt Pearson for this.
* Enforce minimum values of ADShutterOpenDelay and ADShutterCloseDelay based on query of SDK.
* Fix bug when setting MinX and MinY with binning. There was an incorrect factor of 2 present.
Thanks to Hinko Kocevar for this fix.
@hinxx you will need to update your master because of the previous merges.
