Version specific Hadoop profiles

Introduce version specific Hadoop profiles. Introduce a default profile for Hadoop 1 and another for Hadoop 2. Useful when HBase artifacts are built using its Hadoop 2 profile. It is necessary to do this in the Phoenix POM because the Hadoop artifact names for version 2 are different from version 1, and more are required.

Unit tests complete successfully, except for com.salesforce.phoenix.expression.DescColumnSortOrderExpressionTest, which is unrelated to this change as it is failing on forcedotcom/phoenix master already, with 

    mvn -Dhadoop.profile=2 -Dhadoop.version=2.0.4-alpha -Dhbase.version=0.94.8 clean package

where HBase 0.94.8 was built against 2.0.4-alpha and installed into the local Maven cache.