AURORA-299: use system thrift if available

Updates gradle bootstrapThrift to use a system installed Thrift if available
and if it is the same version we are currently using.

Testing Done:
ran build with and without Thrift installed

Bugs closed: AURORA-299

Reviewed at https://reviews.apache.org/r/20246/
AURORA-267: Add container to popover to avoid clipping issue

Reviewed at https://reviews.apache.org/r/20344/
Role and Job pages using new Angular UI.

Bugs closed: AURORA-281

Reviewed at https://reviews.apache.org/r/20512/
Optionally use system-installed thrift in build.gradle, use this in vagrant devcluster.

Bugs closed: AURORA-299

Reviewed at https://reviews.apache.org/r/20238/
Replace sed command with linux and OSX-friendly perl expression.

Bugs closed: AURORA-344

Reviewed at https://reviews.apache.org/r/20571/
Extend the client configuration plugin architecture.

Plugins can now run code at three key points:
- Before arguments are processed and execution is dispatched to a command.
- After argument processing and dispatch, but before execution.
- After execution.

This allows plugins to perform initialization required for argument processing,
and for post-execution cleanups and synchronizations.

Bugs closed: aurora-332

Reviewed at https://reviews.apache.org/r/20521/
Add a "get version" API method. (This is needed for a logging-related change for twitter.)

While I'm in there, fix a bug in "job list".

Reviewed at https://reviews.apache.org/r/20490/
AURORA-132: Cron system based on Quartz

This introduces a new cron system based on Quartz and removes the
NoopCronModule.

Testing Done:
./gradlew build

Bugs closed: AURORA-132

Reviewed at https://reviews.apache.org/r/19767/
End to end test should not look at the number of html lines.

Testing Done:
end-to-end test

Reviewed at https://reviews.apache.org/r/20629/
Implementing Scheduler SLA metrics.

High level overview:
- MetricCalculator runs periodically (every minute), pulls all task history,
  packages it into SlaInstance list and updates stats;
- Stat calculation is handled by a pair of: SlaAlgorithm and a set of
  applicable SlaGroups (logical groupings by job, cluster, resource and etc.);
- Stat name is generated by combining group and algorithm name parts.

Bugs closed: AURORA-293

Reviewed at https://reviews.apache.org/r/20398/
Revert "AURORA-132: Cron system based on Quartz"

This reverts commit c285f2f83dc769143bc4a3be67e3d53b8fc51418.
Fix compilation of SlaGroup
Include inactive tasks when computing job summaries

Currently, the getTasks query was only fetching tasks in active status.
Updated the code to fetching all tasks for getJobSummary.

Testing Done:
Tested on laptop.

Bugs closed: AURORA-338

Reviewed at https://reviews.apache.org/r/20573/
AURORA-48: Rename documentation filenames in associated links to be SEO friendly

Bugs closed: AURORA-48

Reviewed at https://reviews.apache.org/r/20641/
AURORA-265: Add missing tooltips for task states in dictionary.js

Bugs closed: AURORA-265

Reviewed at https://reviews.apache.org/r/20146/
Upgrade pants and commons, fix python thrift namespace so that it does not conflict.

Pins twitter.common on 0.3.0 (save twitter.common.python which is released
out of band.)

Upgrades aurora to twitter.pants 0.0.21 which uses
twitter.common.python==0.5.4 and produces wheels.

Updates the thrift python namespaces so that the autogenerated python
artifacts do not clobber each other.

Reviewed at https://reviews.apache.org/r/20583/
Remove unused mootools dependency

While looking through our dependencies I noticed we don't use this
anymore.

Testing Done:
git grep mootools

Bugs closed: AURORA-147

Reviewed at https://reviews.apache.org/r/20678/
Adding my gpg key.

Reviewed at https://reviews.apache.org/r/20682/
Fixing broken HistoryPruner

Bugs closed: AURORA-359

Reviewed at https://reviews.apache.org/r/20689/
AURORA-234: Replace HTML tables in docs with markdown

Testing Done:
Generated the Aurora site using Middleman. Everything renders correctly, though I've updated the Jira ticket with a comparison between the two rendered tables.

Commit on Github: https://github.com/protochron/incubator-aurora/commit/558a5a6a2f15a82e51ef7bf6d17288f67ff11a97

Bugs closed: AURORA-234

Reviewed at https://reviews.apache.org/r/20027/