Added kotlin duplication checks

[hershamin]

No description provided.

[larkinscott]

Tested this against 30 Kotlin OSS repos. One thing I noticed is that we probably want to exclude the copyright/comments section from duplication analysis. You'll see below that it's being flagged on almost every file:

--- :git: pulling shadowsocks/shadowsocks-android
+++ :codeclimate: :sleuth_or_spy: analyzing shadowsocks/shadowsocks-android
Starting analysis

== mobile/src/androidTest/java/com/github/shadowsocks/acl/AclTest.kt (1 issue) ==
1-19: Similar blocks of code found in 71 locations. Consider refactoring. [duplication]

== mobile/src/androidTest/java/com/github/shadowsocks/database/ProfileTest.kt (1 issue) ==
1-19: Similar blocks of code found in 71 locations. Consider refactoring. [duplication]

== mobile/src/androidTest/java/com/github/shadowsocks/utils/SubnetTest.kt (4 issues) ==
10: Similar blocks of code found in 4 locations. Consider refactoring. [duplication]
11: Similar blocks of code found in 4 locations. Consider refactoring. [duplication]
12-13: Similar blocks of code found in 4 locations. Consider refactoring. [duplication]
14-15: Similar blocks of code found in 4 locations. Consider refactoring. [duplication]

== mobile/src/main/java/com/evernote/android/job/JobConstants.kt (1 issue) ==
1-19: Similar blocks of code found in 71 locations. Consider refactoring. [duplication]

== mobile/src/main/java/com/github/shadowsocks/AboutFragment.kt (2 issues) ==
1-19: Similar blocks of code found in 71 locations. Consider refactoring. [duplication]
44: Similar blocks of code found in 3 locations. Consider refactoring. [duplication]

== mobile/src/main/java/com/github/shadowsocks/App.kt (6 issues) ==
1-19: Similar blocks of code found in 71 locations. Consider refactoring. [duplication]
73: Similar blocks of code found in 3 locations. Consider refactoring. [duplication]
142: Similar blocks of code found in 2 locations. Consider refactoring. [duplication]
176-177: Similar blocks of code found in 3 locations. Consider refactoring. [duplication]
178-179: Similar blocks of code found in 3 locations. Consider refactoring. [duplication]
180-181: Similar blocks of code found in 3 locations. Consider refactoring. [duplication]

We should be able to do this from the DEFAULT_FILTERS constant.

[hershamin]

@larkinscott With the latest commit, the issue of comparing comment docs is fixed.

[larkinscott]

Thanks for pointing that out @zenspider! I trimmed the comment sections in the specs a bit.

[larkinscott]

Trimmed some comments in the specs. Overall, ran it against a large set of OSS projects and the results look good!