merging with lbjava's ilp-solver interface

Changes:

• merges the two ILPSolver interfaces (in this package and the one in LBJava)
• merging the two gurobi solvers: for most of the syntax I have used that of LBJava's.

If this get's merged, we can remove IlpSolver.java, GurobiHook.java and oJAlgoHook.java from lbjava and add this illinios-inference as LBJava's dependency.

FYI @mssammon

pom.xml

@@ -27,11 +27,6 @@
 			<artifactId>junit</artifactId>
 			<version>4.12</version>
 		</dependency>
-		<dependency>
-			<groupId>org.slf4j</groupId>
-			<artifactId>slf4j-api</artifactId>
-			<version>1.7.12</version>
-		</dependency>
 		<dependency>
 			<groupId>com.gurobi</groupId>
 			<artifactId>gurobi</artifactId>
@@ -48,17 +43,6 @@
 			<artifactId>illinois-core-utilities</artifactId>
 			<version>3.0.51</version>
 		</dependency>
-		<dependency>
-			<groupId>edu.illinois.cs.cogcomp</groupId>
-			<artifactId>illinois-sl-core</artifactId>
-			<version>1.0.2</version>
-			<exclusions>
-				<exclusion>
-					<artifactId>guava</artifactId>
-					<groupId>com.google.guava</groupId>
-				</exclusion>
-			</exclusions>
-		</dependency>
 		<dependency>
 			<groupId>org.ojalgo</groupId>
 			<artifactId>ojalgo</artifactId>