update gradle-api artifact to version 1.6 this is required to make kotlin gradle plugin compatible with upcoming Gradle 2.0
cleanup Gradle API deprecation warnings to make plugin compatible with upcoming Gradle 2.0. This includes moving minimum compatible version from 1.4 to 1.6
Bug Fix: KT-4613

Fix replace with infix function intention to be inapplicable in the
case of package function calls, such as “kotlin.io.println(“”).”
Bug fix in intention to move lambda outside parentheses, handles commas better
Eval4j: get value from top of stack, not after local variables
Deprecated java methods are not shown as deprected in kotlin
#KT-4993 Fixed
Make call return JetElement instead of PsiElement
Evaluate expression: allow to call invisible members
 #KT-4935 Fixed
Evaluate expression: clarify error message when there are conflicts from extract function
Minor, fix warning
Minor: make properties private
Parser for JetBlockCodeFragment
Evaluate expression: evaluate block of code (CODE_BLOCK mode)
Completion and highlighting for blockCodeFragment
Evaluate expression: check for syntactic errors
Add getSignificantElement method in JetCodeFragment
Make SpecifyTypeExplicitlyAction inapplicable for code fragments
Follow up for PR #458: Generate test data
Expression code fragments supported in KotlinResolveCache
Support block code fragments in KotlinResolveCache