Update .gitignore

- ignore project.properties
remove project.properties
develop 1.7.0 merge
Changed method of activating preferred exchange.

Instead of using integer index offsets for storing the preferred exchange tab, each tab is now "tagged" with the exchange and stored as a preference item. This will allow future enhancements to allow specifying the visibility and tab re-ordering.

Also includes code to migrate from the old integer index method to the new tab tag method.
Fixed default value for preferred exchange.
Merge remote-tracking branch 'origin/develop'
Merge remote-tracking branch 'upstream/develop' into develop

Conflicts:
	res/values/exchanges.xml
	src/com/veken0m/bitcoinium/MainActivity.java
alternating row colors and layout tweaks
use https for Bitcoinium.com and Bitcoinity
update XChange and resCU jars
Release the Kraken!
fix 4 digits display for bid/ask on widget
Eligius mining pool
Widget tap now selects Exchange or Pool tab
Merge remote-tracking branch 'upstream/develop' into develop

Conflicts:
	res/values/exchanges.xml
	src/com/veken0m/bitcoinium/MainActivity.java
Changed tab keys from integer indexes to strings
Replace index-based ID with string-based ID

Changed usage of index-based IDs in widget and Exchange class with string-based IDs used elsewhere.
Merge pull request #15 from zerodivide1/develop

Develop
Update README.md
improve Activity lifecycle management