runtime support running on different versions of spark

[yaooqinn]

#67 makes kyuubi support original spark release package with specified maven options. for instance, -Pspark-2.2 gives us a kyuubi runnable package twards spark2.2.x.

But still, we need offer a more compatible way to support different versions of Spark at runtime.

Fix version conflict regression in #67

[codecov]

Codecov Report

Merging #71 into master will increase coverage by 3.01%.
The diff coverage is 44.11%.

@@             Coverage Diff             @@
##             master     #71      +/-   ##
===========================================
+ Coverage     24.19%   27.2%   +3.01%     
  Complexity       84      84              
===========================================
  Files            63      64       +1     
  Lines          2625    2823     +198     
  Branches        377     396      +19     
===========================================
+ Hits            635     768     +133     
- Misses         1927    1974      +47     
- Partials         63      81      +18

Impacted Files	Coverage Δ	Complexity Δ
src/main/scala/org/apache/spark/SparkEnv.scala	66.66% <35.71%> (ø)	0 <0> (?)
.../main/scala/org/apache/spark/KyuubiSparkUtil.scala	87.23% <83.33%> (-0.58%)	0 <0> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update dd09f56...a8591ac. Read the comment docs.