Docs: make the welcome page more obvious

Closes #73.
Update to elasticsearch 1.2.0

Closes #68.

(cherry picked from commit 33f61e8)
Adding new files while scanning could raise a non caught exception

 This patch tries to reduce that risk although it does not totally removes it.

 When adding a new file to the directory which is scanned by the river could fail when closing the river at the same time.

 We need to check if the river is still opened before adding anything to the bulk and fail with a clean message otherwise.

 That kind of error could appear as well:

 ```
 2014-08-11 13:06:56,398 WARN  - [node_1] [fs][test_stop_river] failed to get _lastupdate, throttling....
 org.elasticsearch.ElasticsearchIllegalStateException: Future got interrupted
 	at org.elasticsearch.action.support.AdapterActionFuture.actionGet(AdapterActionFuture.java:48)
 	at fr.pilato.elasticsearch.river.fs.river.FsRiver$FSParser.getLastDateFromRiver(FsRiver.java:440)
 	at fr.pilato.elasticsearch.river.fs.river.FsRiver$FSParser.run(FsRiver.java:404)
 	at java.lang.Thread.run(Thread.java:745)
 Caused by: java.lang.InterruptedException
 	at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:996)
 	at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1303)
 	at org.elasticsearch.common.util.concurrent.BaseFuture$Sync.get(BaseFuture.java:274)
 	at org.elasticsearch.common.util.concurrent.BaseFuture.get(BaseFuture.java:113)
 	at org.elasticsearch.action.support.AdapterActionFuture.actionGet(AdapterActionFuture.java:45)
 	... 3 more
 ```

 Or that ones as well:

 ```
 2014-08-11 13:16:56,593 WARN  - [node_4] [fs][test_stop_river] Error while indexing content from /Users/dpilato/Documents/Elasticsearch/dev/fsriver/target/test-classes/test_stop_river
 2014-08-11 13:16:56,595 DEBUG - [node_4] [fs][test_stop_river] Exception for /Users/dpilato/Documents/Elasticsearch/dev/fsriver/target/test-classes/test_stop_river is org.elasticsearch.ElasticsearchIllegalStateException: Future got interrupted
 2014-08-11 13:10:42,776 INFO  - [node_0] [_river] update_mapping [test_stop_river] (dynamic)
 2014-08-11 13:10:42,797 WARN  - [node_2] [_river] no index mapper found for field: [fs.docadded] returning default postings format
 2014-08-11 13:10:42,798 WARN  - [node_2] [_river] no index mapper found for field: [fs.docdeleted] returning default postings format
 2014-08-11 13:10:42,799 WARN  - [node_2] [_river] no index mapper found for field: [fs.feedname] returning default postings format
 2014-08-11 13:10:42,799 WARN  - [node_2] [_river] no index mapper found for field: [fs.lastdate] returning default postings format
 ```

 or

 ```
 2014-08-11 14:22:29,757 WARN  - [node_1] [fs][test_stop_river] Error executing bulk
 java.lang.InterruptedException
 	at java.util.concurrent.locks.AbstractQueuedSynchronizer.doAcquireSharedInterruptibly(AbstractQueuedSynchronizer.java:996)
 	at java.util.concurrent.locks.AbstractQueuedSynchronizer.acquireSharedInterruptibly(AbstractQueuedSynchronizer.java:1303)
 	at java.util.concurrent.Semaphore.acquire(Semaphore.java:317)
 	at org.elasticsearch.action.bulk.BulkProcessor.execute(BulkProcessor.java:288)
 	at org.elasticsearch.action.bulk.BulkProcessor.executeIfNeeded(BulkProcessor.java:267)
 	at org.elasticsearch.action.bulk.BulkProcessor.internalAdd(BulkProcessor.java:249)
 	at org.elasticsearch.action.bulk.BulkProcessor.add(BulkProcessor.java:236)
 	at org.elasticsearch.action.bulk.BulkProcessor.add(BulkProcessor.java:232)
 	at org.elasticsearch.action.bulk.BulkProcessor.add(BulkProcessor.java:218)
 	at fr.pilato.elasticsearch.river.fs.river.FsRiver$FSParser.esIndex(FsRiver.java:863)
 	at fr.pilato.elasticsearch.river.fs.river.FsRiver$FSParser.indexFile(FsRiver.java:779)
 	at fr.pilato.elasticsearch.river.fs.river.FsRiver$FSParser.addFilesRecursively(FsRiver.java:536)
 	at fr.pilato.elasticsearch.river.fs.river.FsRiver$FSParser.run(FsRiver.java:410)
 	at java.lang.Thread.run(Thread.java:745)
 ```

 Closes #75.

(cherry picked from commit e5860c9)
Docs: add debug information

Configuring `logging.yml` is not something obvious. We need to document it.

Closes #77.

(cherry picked from commit ce3ca8b)
Files not correctly added/removed from index on Windows platform

Updated concatenation of filepath and filename to prevent double backslash

On windows machines the last modified date is not updated when you copy a file.
For copied files the creation date has to be used. This does not cover renaming
files. Using java.nio library to get file creation date. This requires java 7

Closes #32.
Closes #60.
Closes #65.

(cherry picked from commit a8a4bd8)
Update for elasticsearch 1.2
Update to elasticsearch 1.3.0

Closes #74.
Update to elasticsearch 1.4.0

Closes #76.
Release tool temp dir must be ignored

(cherry picked from commit 9f13999)