Merge pull request #39 from hzsweers/master

Better support for retrieving mapping.txt file
Fix signing with grade 2.1
Fix typo
Better logging
[Gradle Release Plugin] - pre tag commit:  '2.2'.
[Gradle Release Plugin] - new version commit:  '2.3-SNAPSHOT'.
Add variantToReleaseType
Fixes #38
Fix if clause
Merge pull request #40 from x2on/variantToReleaseType

Add variantToReleaseType
[Gradle Release Plugin] - pre tag commit:  '2.3'.
[Gradle Release Plugin] - new version commit:  '2.4-SNAPSHOT'.
add variantToApiToken
Merge pull request #41 from kyhule/variant-to-api-token

add variantToApiToken
[Gradle Release Plugin] - pre tag commit:  '2.4'.
[Gradle Release Plugin] - new version commit:  '2.5-SNAPSHOT'.
Source and Target Compatibility is now explicitly set to Java 1.6.
Plugin is now building to Android Gradle Plugin 0.14.+.
Added variantToNotes and variantToNotesType.
Reverted Gradle wrapper to version 2.1.
Merge pull request #43 from diegotori/master

variantToNotes, variantToNotesType, plus Java and Android Gradle Plugin compatibility fixes.