added first iter of proper-nouns pig solution

exercises/intro-to-pig/solution/proper_nouns.pig

@@ -0,0 +1,24 @@
+
+-- Load in the jar that contains our UDFs
+REGISTER textudf.jar;
+
+-- load the (word, sentence) pairs in.
+bard = LOAD 'input_idx' USING PigStorage(',') AS (word, sentence);
+
+-- Ignore anything that isn't a Capital word. We ignore FULLY capitalized words,
+-- as well as the word 'I'.
+caps = FILTER bard BY word matches '[A-Z][a-z][a-zA-Z]*';
+
+-- Find all instances where the word is capitalized, and doesn't start its sentence
+not_starting = FILTER caps BY NOT textudf.StartsWith(sentence, word);
+
+-- throw away the sentence, we just want the word part of the record.
+justword = FOREACH not_starting GENERATE word;
+
+-- deduplicate...
+nodups = DISTINCT justword;
+
+-- and write out the results.
+STORE nodups INTO 'proper_nouns';
+
+