IEEE concurrent implementation

[Bruno Cartaxo]

Implement the IEEE search provider concurrently in order to access result pages in different threads improving the search performance.

Some sugesttions of eclipse plugins to analyse the reviewer performance:

1. JVM Monitor - Plugin for JVM profiling
   http://www.jvmmonitor.org/
2. Memory Analyzer - Plugin to analyze JVM memory dumps
   http://www.eclipse.org/mat/