README: No double empty lines [minor]

Author: hoijui

README.markdown

@@ -165,7 +165,6 @@ There are some associated JUnit tests, which also contain code that may illustra
 how to use the library.
 They can be run with `mvn test`.
 
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 ## Release a SNAPSHOT (devs only)
 
 To release a development version to the Sonatype snapshot repository only:
@@ -193,7 +192,6 @@ you need to add this to your _pom.xml_:
 	</repositories>
 ```
 
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 ## Release (devs only)
 
 ### Prepare "target/" for the release process
@@ -290,10 +288,8 @@ This does the following:
 * deploy into Sonatype staging repository
 * promote it on Maven Central repository (may have a delay of up to 4h)
 
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 ## Thanks
 
 Thanks to John Thompson for writing the UI (demo application),
 Alexandre Quessy for the PD demo,
 and to Martin Kaltenbrunner and Alex Potsides for their contributions.
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